![]() This is a titillating topic to cover. Let's start with the female reproductive system because... well... it's the most mystical in my mind. I'm currently reading the book "Blood, Bread and Roses: How Menstruation Created the World" by Judy Grahn. Here's a juicy quote from the preface to kick us off on this exciting topic: "Menstrual blood is the only source of blood that is not traumatically induced. Yet in modern society, this is the most hidden blood, the one so rarely spoken of and almost never seen, except privately by women, who shut themselves in a little room to quickly and many cases disgustedly change their pads and tampons, wrapping the bloodied cotton so it won't be seen by others, wrinkling their faces at the odor, flushing or hiding the evidence away. Blood is everywhere, and yet the one, the only, the single name it has not publicly had for many centuries, is menstrual blood. Menstrual blood, like water, just flows. Its fountain existed long before knives or flint; menstruation is the original source of blood. Menstruation is blood's secret name. All blood is menstrual blood." I've been thinking about this idea for a long time. We are all made up of menstrual blood so why is our society so bent out of shape about acknowledging menstrual blood's existence? We're made up of periods. You're a period. I'm a period. I want to talk about your period and my period and embrace it with you, and me and people on the street. When I first got my period my mother was too shy to talk to me about it. She left pads on my desk when I was at field hockey practice and it was a forbidden subject. I still carry some resentment about that. I'm still rebelling at her shame by openly talking about periods and vaginas whenever I can. I want to celebrate this juicy, powerful, vulnerable, potent part of my life... Judy Grahn writes, "According to anthropologist Chris Knight, the menstrual cycle of primates varies greatly, some species having a seven-day cycle, while others go all the way to thirty-nine days. Only the rhesus macaque, at a twenty-nine day cycle, is close to the human pattern. Only the human cycle, at twenty-nine and a half days, coincides with the cycle of the moon." In times past, women’s periods corresponded more closely with the phases of the moon, with ovulation at full moon and menses at the new moon. It stands to reason that before the advent of artificial light, hormone fluctuations may have been more closely governed by not only diurnal cycles (as with melatonin and cortisol), but by regular monthly cycles. Who among us has not witnessed the powerful effect that the moon’s phases exert on earth’s largest water body, the ocean? It is no stretch to suppose the ebb and flow of fluid in our own bodies — largely composed of water — would be similarly influenced. Uffffff. So magical. ![]() PEOPLE WITH VAGINAS STUFF So, let’s get into the nitty gritty science about menstruation and what it’s all about. Quick note: This post is imperfect. At times I try to leave some space in my wording of male versus female systems to account for the fact that some men have female reproductive systems and vice versa. Most of the time I don't. I hope those reading can get the information they need without getting offended or stuck in the terminology. Unlike the male reproductive system, the female system keeps almost all of their organs hidden. The two ovaries provide a nourishing home for eggs-in waiting, also called follicles. The female system is born with a set number of follicles that have the potential to be chosen as the star egg of a cycle. About four months prior to the cycle, a follicle is chosen as the "queen bee egg" and "groomed" for its role. Oogenesis is the creation of an ovum (egg cell). It is the female form of gametogenesis and the male equivalent (which we'll get into later) is spermatogenesis. The female process involves the development of the various stages of the immature ovum. The two major female hormones, estrogen and progesterone, are produced in the ovaries under the direction of pituitary hormones called follicle-stimulating hormone (FSH) and luteinizing hormone (LH). The production of FSH and LH come at the urging of the hypothalamus's gonadotropin-releasing hormones (GnRH). During each cycle an egg is released from one of the ovaries and travels down the fallopian tube, and enters the uterus, where it hopes to meet up with some sexy spermies to create a baby. If that occurs, the duo settle down in the uterus which then becomes an incubator. If not, the egg travels out of the uterus, through the cervix and vagina to exit the body during menstruation. ![]() THE CYCLE Day 1 to 14: Estrogen Dominates The first day of the cycle begins on the first day of menses. When pregnancy doesn't happen, progesterone will have just dropped, oxytocin surges and the uterine lining begins to slough off. In the ovaries a follicle awaits its special moment in the pageant of eggs waiting to be chosen. In the four months prior when the egg was first chosen from the pool of follicles, the egg gets showered with vitamins, nutrients, and hormones so that the egg can be at peak vitality to meet up with some sperm. The chosen follicle (and soon to be egg) produces estrogen in the ovaries via stimulation from FSH in the brain. The estrogen that gets secreted triggers the body to begin rebuilding the uterine lining once the old stuff has come off. In addition, the estrogen that gets secreted by the follicle strengthens and lubricates vaginal tissue, protects against bone loss and keeps one mood in a vital place and bolsters immunity. Day 14: Ovulation Around day 14 a special day arrives. A surge of oxytocin - the "releasing hormone" - releases the follicle from the ovary, and it becomes THE EGG that travels down the fallopian tubes into the uterus to hang out with sperm or be released from the body. Oxytocin has a variety of effects on the body including carnal DESIRE. Many folks with a female reproductive system report feeling pretty horny around this time in the cycle. Oxytocin increases libido and aids climax and reversely, sex and foreplay help INCREASE oxytocin action. At ovulation, estrogen dips and progesterone kicks into gear. You will notice a dip in one's basal body temperature right before ovulation and then rises a few tenths of a degree afterward. In the days after ovulation, the body boosts its production of cervical mucus to make the system a more welcoming environment for sperm and the organ that helps deliver it. Day 14 to 28: Progesterone Dominants Now that the egg has left the ovary, progesterone (stimulated by LH) is produced by the corpus luteum, the empty nest that the egg departed from in the ovary. Similar to estrogen, progesterone also keeps mood and the immune system in vital shape, but its primary job is to finish the mission that estrogen began. Progesterone starts preparing the uterus lining to either incubate and grow a baby or slough off well in the next cycle. Body temperature remains a bit higher during this part of the cycle and folks tend to be hungrier at this time. The body is attempting to hold onto nutrients just in case one might need them for a growing fetus. If conception occurs the basal body temperature rises a few notches due to a pregnancy related progesterone surge as well as other changes including breast swelling and mood changes. If pregnancy does not occur, the basal temperature will drop when the corpus luteum ceases to excrete progesterone. Oxytocin surges and the cycle begins anew. Overview The menstrual cycle does not always go so smoothly. Hormones teeter during periods like adolescence and menopause as the reproductive system kicks on and off the baby-making modes. Throughout the reproductive years other factors influence the cycle like environmental factors, stress, diet, etc. Time of ovulation Women often believe that ovulation occurs mid-cycle. It actually occurs 12-16 days before the next period starts. So, although a woman with a 28-day cycle may ovulate mid-cycle (between day 12 and day 16), a woman with a 36-day cycle will ovulate between day 20 and day 24. For women with regular cycles, an easy way to approximate the time of ovulation is to subtract 16 from the number of days in the cycle and then add 4. This will calculate the span of days in which ovulation is most likely to occur. For instance, a woman with a 22-day cycle is most likely to ovulate between days 6 and 10 of her cycle (22-16 = 6 (+4 =10). Ovulation and conception Following ovulation, the egg lifespan can be up to 24 hours, but is usually between six and 12 hours (4). In contrast, sperm generally survive for three days, but can live inside the vagina for up to five days if optimal fertile cervical mucus is present. Pregnancy can therefore result from intercourse that occurs within a woman’s fertile window (from as early as five days before ovulation, until up to 24 hours following ovulation). MOON MUSINGS I think we’re approaching a moment of major reclamation of the reason and ritual surrounding female body and blood. While my mother approached this subject with shame and avoidance, I hope to pass on the tradition of honoring and respecting this important and mystical aspect of the female body. Facebook recently removed a picture of a woman with menstrual blood on her pants posted by a feminist activist. Many people were angered by facebook's decision to remove an image related to female menstruation and I think some much needed dialogue is occurring right now in regards to menstruation, sexual assault and the patriarchy. I hope to continue to be part of this stirring opennes and conversation. ![]() People with Penis Stuff Let’s move our attention briefly to the male reproductive organs and glands and the process which produces sperm. Spermatogenesis is a process which produces mature male gametes, commonly called sperm but specifically known as spermatozoa, which are able to fertilize the counterpart female gamete, the oocyte, during conception to produce a single-celled individual known as a zygote. This is the cornerstone of sexual reproduction and involves the two gametes both contributing half the normal set of chromosomes to result in a chromosomally normal zygote. Male reproductive capacity depends on testosterone, a steroid hormone produced by Leydig cells located between the seminiferous tubules within the testes. The production and secretion of testosterone depends on three hormones:GnRH from the hypothalamus and LH and FSH from the anterior pituitary gland. Interestly, the names for LH and FSH came from their functions in the female, but they are active hormones in the male as well. Negative feedback loops involving the hypothalamus, the pituitary and the testes maintain a fairly constant blood concentration of testosterone and thus a consistent rate of sperm production. ![]() Semen contains sperm and the secretions of three glands: the seminal vesicles, the prostate gland, and the bulbourethral glands. The seminal vesicles produce seminal fluid, a watery mixture containing fructose and prostaglandins that represents about 60% of the volume of sperm. Fructose, a carbohydrate, provides the sperm with a source of energy. The prostate gland contributes an alkaline fluid which helps temporarily raise the vaginal pH to 6 (normal vaginal pH is 3.5 to 4) which is optimal for sperm. Finally, the bulbourethral glands secrete mucus into the urethra during sexual arousal. The mucus provides lubrication for sexual intercourse and also washes away traces of acidic urine in the urethra before the sperm arrive. To enhance the possibility of sperm survival, the sperm are not mixed with seminal and prostate fluids until the moment of ejaculation. Tens of millions of sperm are formed every day throughout the person with a penis’ adult life. The sites of sperm production are the paired testes. Shortly before birth the testes descend into the scrotum where the temperature is regulated for the developing sperm. Spermies develop best at temperatures a few degrees cooler than body temperature thus the scrotum is an ideal nest because it can contract and bringing the testes closer to the warmth of the body or during hot weather the scrotum can relax, hanging at a cooler temperature away from the body. Each testis is only about 2 inches long but it contains over 100 years of tightly packed seminiferous tubules where the sperm form. The several hundred seminiferous tubules join to become the epididymis, a single coiled duct just outside the testis. The epididymis joins the long ductus (vas) deferens, which eventually joins the duct from the seminal vesicle to become the ejaculatory duct. The newly formed sperm are not fully mature (they cannot yet swim) when they leave the seminiferous tubules. Their ability to swim develops in both the epididymis and the ductus deferens where the sperm is stored until ejaculation. When the male or person with a penis reaches sexual climax and ejaculates, rhythmic contractions of smooth muscle propel the sperm through the short ejaculatory duct and finally through the urethra, which passes through the penis. REPRODUCTIVE VITALITY
Maria Noel Groves makes a great point in her book, Body Into Balance, an Herbal Guide to Holistic Self-Care. I’ve posted it here: “Reproductive health serves as a barometer for your overall health in at least two ways. First, your reproductive system comes last in the pecking order of your body’s priorities. You need to be able to breathe, circulate blood, digest, detoxify, et. cetera, in order to survive. The ability to make babies (the ultimate purpose of the reproductive system) is superfluous, something to when everything else is going great. After all, making and raising babies taxes your body and mind and certainly isn’t necessary (from a pragmatic perspective) for your survival. For this reason, reproductive issues can be the canary in the coal mine for bigger-picture problems. Stress, sleep deprivation, nutrient deficiencies, thyroid wobbles, obesity, cardiovascular disease, and blood sugar issues are a just a few things that can send your hormones swinging and muck up the reproductive wiring. In a slightly different yet connected way, your reproductive system functions as a loudspeaker for your body’s overall health. This is particularly true for women, whose complicated and difficult to ignore cycles expand and contract each month and are easily thrown awry. Imbalances elsewhere amplify during weak points in the monthly cycle, most commonly the days before you get your period. Men are equally affect, but because their hormones and cycles are a little less obvious- at least until middle age, when they manifest as prostate and sexual problems- it’s easy to ignore the warning signs.” Luckily, there are ways to help coax the body back into balance. A good diet, adequate sleep and regular exercise set the stage for vitality and health but herbs have a place in assisting us too. From prostate support herbs and male health tonics to adaptogens and circulatory herbs, there are plenty of ways to support the male reproductive system with herbs. Female bodied people can benefit from iron-rich herbs, bone supportive herbs and herbs to support estrogen balance and pain support during menstruation.
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Parts of the Respiratory System When you inhale, air enters through your nose or your mouth. Did you know that your nose does more than serve as a passageway for respiration? Ode to the nose! The nose also: -Contains receptors for your sense of smell -Filters inhaled air and screens out some foreign particles -Moistens and warms incoming air -Provides a resonating chamber that helps give your voice its characteristic tone Cool. Thanks, nose! From there, incoming air next enters the pharynx (throat), which connects the mouth and the nasal cavity to the larynx (voice box). The upper pharynx extends from the nasal cavity to the roof of the mouth. Into it open the two auditory tubes that drain the middle ear cavities and equalize air pressure between the middle ear and outside air. The lower pharynx is a common passageway for both food and air. Food passes through on its way to the esophagus, and air flows on its way to the lower respiratory tract. The lower respiratory tract includes the larynx, the trachea, the bronchi and the lungs with their bronchioles and alveoli. The trachea is the "windpipe" that extends from the larynx to the left and right bronchi. Like the nasal cavity, the trachea is lined with cilia-covered epithelial tissue that secretes mucus. The mucus traps foreign particles and the cilia move them upward, away from the lungs. The trachea branches into two airways called the right and left bronchi (singular: bronchus...hehe) as it enters the lung cavity. Like the branches of a tree, the two bronchi divide into a network of smaller and smaller bronchi. The walls of bronchi contain fibrous connective tissue and smooth muscle reinforced with cartilage. As the branching airways get smaller and smaller the amount of cartilage declines. By definition, the smaller airways that lack cartilage are called bronchioles. In addition to air transport, the bronchi and bronchioles have several other functions in addition to air transport. They also clean the air, warm it up to body temperature and lovingly saturate it with water vapor before it reaches the delicate gas-exchange surfaces of the lungs. Most bronchi and bronchioles are lined with ciliated epithelial cells and occasional mucus-secreting cells. These cells trap particles and then sweep them upward toward the pharynx so they can be swallowed. The respiratory bronchioles eventually become alveolar ducts. Basically, the lungs are a system of branching airways that end in 300 million tiny air-filled sacs called alveoli. It is in these sacs where gas exchange takes place. Alveoli are arranged in clusters at the end of every terminal bronchiole, like wild grapes dangling from a stem. A single alveolus is a thin bubble of living squamous epithelial cells only one layer thick YET their combined surface area is nearly 40 times the area of our skin. This tremendous amount of surface area and the thinness of the squamous type of epithelium facilitate gas exchange with nearby capillaries. Within each little alveolus, certain epithelial cells secrete a lipoprotein called surfactant that coats the interior of the alveoli and reduces surface tension. Surface tension happens because of the attraction of water molecules towards each other Without surfactant, the force of surface tension could collapse the alveoli. My friends and I slaughtered a sheep last fall for meat and when I touched the lungs of our recently departed friend I was struck by how soft and frothy they were. It was surprising to me at the time - that lungs are mostly air! The lungs are organs consisting of supportive tissue enclosing the bronchi, bronchioles, blood vessels and the areas where gas exchange occurs. They occupy most of the thoracic cavity. There are two lungs, one on the right side and one of the left side, separated from each other by the heart. Each lung is enclosed in two layers of thin epithelial membranes called the pleural membranes. One of these layers represents the outer lung surface and the other lines the thoracic cavity. The pleural membranes are separated by a small space called the pleural cavity, that contains a very small amount of watery fluid. The fluid reduces friction between the pleural membranes and the lungs and chest wall during breathing. The Process of Breathing Breathing involves getting air into and out of the lungs in a cyclic manner that requires muscular effort. The lungs themselves don't have any skeletal muscle tissue so how does this happen? The lungs expand passively because the surrounding bones and muscles expand the size of the chest cavity. The bones and muscles involved in respiration include the ribs, the intercostal muscles between the ribs, and the main muscle of respiration called the diaphragm, a broad sheet of muscle that separates the thoracic cavity from the abdominal cavity. The intercostal muscles and the diaphragm are skeletal muscles. To understand why air moves into and out of the lungs in a cyclic manner, let's take a look at some general principles of gas pressure and of how gases move: 1. Gas pressure is caused by colliding molecules of gas 2. When the volume of a closed space increases, the molecules of gas in that space are farther away from each other, and the pressure inside the space decreases. Conversely, when the volume in a closed space decreases, the gas pressure increases. 3. Gases flow from areas of higher pressure to areas of lower pressure Overall, the lungs expand and contract only because they are compliant (stretchable) and because they are surrounded by the pleural cavity, which is airtight and sealed. If the volume of the pleural cavity expands, the lungs will expand with it. Inspiration (inhalation) pulls air into the respiratory system as lung volume expands, and expiration (exhalation) pushes air out as lung volume declines again. When the lungs expand, the pressure within them falls relative to the atmospheric pressure and air rushes in. During expiration the lungs become smaller and increasing pressure within them forces air out. During our normal breathing, the act of inspiration is active (requiring energy) and expiration is passive. We normally breathe at about 12 breaths per minute with a tidal volume of 500 ml per breath. Our vital capacity is the maximum amount of air we can exhale after a maximal inhalation. Gas Exchange and Transport Occur Passively Overall, oxygen and carbon dioxide (a waste product of body processes) are exchanged in the tiny air sacs of the alveoli at the end of the bronchial tubes. When a person inhales, oxygen moves from the alveoli to the surrounding capillaries and into the bloodstream. At the same time, carbon dioxide moves from the bloodstream to the capillaries and into the alveoli. The carbon dioxide is removed from the lungs when a person exhales. The lungs are in a constant state of filtering contaminants from the outside air, releasing toxins from the body and balancing the levels of oxygen and carbon dioxide in your body. Interestingly, the bronchial tubes look like an up-side down tree and the respiratory system exists in a dynamic symbiosis with the plant world, using and releasing the opposing gases that keep both alive. It's an exciting connection that we can also use plants to assist us in facing respiratory woes. In our therapeutics class this year, Betzy talked about the following strategies for treating and managing respiratory ailments:
-Open the airways (and improve oxygen utilization) -Reduce histamine and mucus -Soothe irritation and spasms -Rebuild and repair lung tissue -Fight infection -Decrease inflammation -Avoid respiratory irritants Many lung issues, including asthma and bronchitis, involve a constriction and/or spasm of the lungs and bronchi. Many herbs we talked about in class address this but many herbalists consider mullein, elecamane and yerba santa to be the bee's knees in opening the airways. Overreactive immune and histamine response is at the center of many respiratory ailments, including asthma, seasonal allergies, postnasal drip, congestion and others. While an immune-supporting lifestyle can reduce the severity and frequency of an overreactive response, there are herbs that can reduce histamine production and relieve symptoms. Horehound leaf can thin mucus and help clear it from the airways while addressing spasms. Goldenrod contains anti-inflammatory, antihistamine properties and helps thin and drain mucus while toning the mucosal lining. There are a number of demulcent and vulnerary herbs that help counteract dryness, irritation, heat and inflammation while supporting vital tissue and healthy amounts of mucus. Marshmallow root, licorice root and plantain would help here. Wild cherry bark specifically quells dry, irritated, hacking coughs and soothes irritated lungs while reishi and cordyceps have immune-supportive benefits that strengthen respiratory function and structure. Overall, there are many great herbs to help rebuild, repair, fight infection, sooth irritation, open the airways and fight overactive histamine and mucus production. The Urinary System
As I go about my day I frequently consider a rumble or pain in my stomach or the deep beating of my heart but how often do I give my kidneys a second thought? They are forgotten organs tucked away at the back of the abdominal cavity. Yet the kidneys play a vital role in maintaining the constancy of my internal environment, with urine as their primary product. Urine itself serves no purpose, it is simply the end product of the regulation of the internal environment, the waste that is discarded. The Composition of Urine Urination may not seem like a glamorous topic. Why is it so important to your body? Urine removes waste products from the body, helps maintain healthy levels of water and it helps maintain healthy levels of salt and other solutes. Urine is essentially water and solutes. Among the solutes excreted in urine are excess elements and ions, drugs, vitamins, toxic chemicals, and waste products produced by the liver or by cellular metabolism. Some substances, such as water and sodium chloride (salt) are excreted to regulate body fluid balance and salt levels. About the only major solutes not excreted by the kidneys under normal circumstances are the three classes of nutrients (carbohydrates, lipids, and proteins). The kidneys keep these nutrients in the body for other organs to regulate. The Kidneys Kidneys - the main organ of the urinary system! They’re located on either side of the vertebrae column, near the posterior body wall. Each kidney is a dark reddish-brown organ about the size of your fist and shaped like a kidney bean. A renal artery and a renal vein connect each kidney to the aorta and inferior vena cava. Each kidney consists of inner-pyramid-shaped zones of dense tissue (called renal pyramids) that constitute the medulla, and an outer zone called the cortex. At the center of the kidney is a hollow space, the renal pelvis, where urine collects after it is formed. A closer look reveals that the renal cortex and medulla contain long, thin, tubular structures called nephrons. Nephrons share a common final section called the collecting duct, through which urine produced by the nephrons is delivered to the renal pelvis. Each kidney contains approximately a million small functional units of nephrons. An individual nephron consists of a thin hollow tube of epithelial cells, called a tubule, plus the blood vessels that supply the tubule. The function of the nephron is to produce urine. Urine Formation: Nephrons don’t just pick the waste molecules out of blood and excrete them. They remove about 180 liters of fluid from the blood every day (about 2.5 times your body weight) and then return almost all of it to the blood, leaving just a small amount of fluid behind in the tubule to be excreted as urine. An analogy would be: cleaning your room by taking everything out of the room and then putting it all back except for the dust and waste you no longer want. A nephron tubule consists of Bowman’s capsule, where fluid is filtered, and four regions in which the filtrate is modified before it becomes urine: proximal tubule, loop of Henle, distal tubule, and collecting duct. Blood flows to Bowman’s capsule via the renal artery and afferent arterioles. Peritubular capillaries carry the blood to the proximal and distal tubules, and vasa recta supply the loops of Henle and collecting ducts. Glomerular filtration separates plasma fluid and small solutes from larger proteins and blood cells. High blood pressure in the glomerular capillaries drives this process. During tubular reabsorption, nearly all the filtered water and sodium and all the major nutrients are reabsorbed from the nephron tubule. The process beings with the active transport of sodium across the cell membrane located on the capillary side of the tubular cell. Tubular secretion removes toxic, foreign and excess substances from the capillaries. It is essential to the regulation of acid-base balance, potassium balance, and the excretion of certain wastes. Blood balance Blood volume is determined in part by how we retain or excrete water. Increases in blood volume raise blood pressure and decreases in blood volume lower it, so it is critical that the blood volume (and water volume) be maintained. The maintenance of water volume is a function shared by the kidneys, the hypothalamus of the brain and the posterior pituitary gland of the endocrine system. Water balance is achieved by a negative feedback loop that regulates the solute concentration of blood. The control of blood volume also depends on maintaining the the body’s salt balance, which in turn depends on three hormones: aldosterone, renin, and atrial natriuretic hormone (ANH). Aldosterone, a steroid hormone from the adrenal gland, increases the reabsorption of Na+ across the distal tubule, and collecting duct. High concentrations of aldosterone cause nearly all of the filtered sodium to be reabsorbed, so that less than 50 milligrams per day appears in the urine. Low levels of the hormone allow as much as 20-25 grams of sodium to be excreted each day. When we consider that the average North American consumes about 10 grams of sodium daily, we see that aldosterone provides more than enough control over sodium excretion. The Body’s Main Fluid Compartments The fluids of the various tissues of the body are divided into fluid compartments. Intercellular fluid is the fluid found within cells. It is separated into compartments by membranes which encircle the various organelles of the cell. Extracellular fluid usually denotes all the body fluid outside of cells. The extracellular fluid can be divided into two major sub compartments, interstitial fluid and blood plasma. Blood plasma is the straw-colored/pale-yellow liquid component of blood that normally holds the blood cells in suspension. It makes up 55% of total blood volume. Interstitial fluid is a solution that bathes and surrounds the cells. On average, a person has about 11 liters of interstitial fluid, providing the cells of the body with nutrients and a means of waste removal. Transcellular fluid is the portion of total body water contained within epithelial lined spaces. It is the smallest component of extracellular fluid, which also includes interstitial fluid and plasma. Fluids, Electrolytes, Acids and Bases… Plasma osmolality measures the body’s electrolyte-water balance. Buffers are substances that prevent changes in the pH by removing or releasing hydrogen ions. Buffer systems reduce the effect of an abrupt change in hydrogen ion concentration by converting a strong acid or base into a weak acid or base. Buffer systems that help maintain acid-base balance include: sodium bicarbonate, phosphate, and protein. Kidneys and Lungs! The protein buffer system changes the pH of the blood in three minutes or less by changing the breathing rate. A decreased respiration rate decreases the exchange and release of CO2 while there is also less hydrogen and the pH rises. Respiration places a crucial role in controlling pH. In addition to excreting various acid waste products, the kidneys help manage acid-base balance by regulating the blood bicarbonate concentration. They do this by permitting bicarbonate reabsorption from tubular filtrate and by forming additional bicarbonate to replace that used in buffering acids. How this all relates to herbal medicine: For general kidney support it’s important to consider hydration and diuretics. Together they help flush out toxins through kidneys and urine. Some of the classic diuretics that I like include parsley leaf, celery stalks, dandelion leaf, burdock root and nettle leaf. The best way to deliver this medicine to the kidneys is through water. Tea, broth or juice. Or just eating these lovely herbs with your food. Another action to consider when working with kidneys are demulcents. With their soothing, slimy, healing, slippery properties, demulcent herbs are a welcome addition to an herbal formula for the kidneys. In addition to the classics like marshmallow root and slippery elm, there’s also corn silk, a simple safe demulcent for the kidney-urinary system. The digestive system consists of all the organs that share the common function of getting nutrients into the body. It includes a series of hollow organs extending from the mouth to the anus: the mouth, pharynx, esophagus, stomach, small intestine, large intestine, rectum and anus. These organs form a hollow tube called the gastrointestinal (GI) tract. The space within this special, hollow tube - the area through which food and liques travel - is called the lumen. The digestive system also includes four accessory organs - the salivary glands, liver, gallbladder, and pancreas. From the esophagus to the anus, the walls of the GI tract share common structural features. The walls of the GI tract consist of four layers of tissue:
Some of the organs of the GI tract are separated from each other by thick rings of circular smooth muscle called sphincters. When these sphincters contract they can close off the passageway between organs. In practical terms, the digestive system is a huge, honkin’ assembly line that starts with huge chunks of raw material (food) and takes them apart so that the nutrients in food can be absorbed into the body. The digestive system accomplishes this task with five basic processes: chewing through mechanical processing and movement; fluid secretion of fluids, digestive enzymes, acid, alkali, bile and mucus; digestion in which the contents of the lumen are broken down into smaller particles; absorption in which nutrient molecules pass across the mucosal layer of the GI tract into the blood or lymph and elimination, in which undigested material is eliminated from the body via the anus. The smooth muscle of the GI tract produces two kinds of motility, called peristalsis and segmentation. Peristalsis propels food forward through a peristaltic wave of contraction ripples through the organs of the GI tract, mixing the contents of the stomach and pushing things forward. Segmentation mixes food while short sections of smooth muscle contract and relax in seemingly random fashion. The result is a back and forth mixing of the contents of the lumen. Food particles are pressed against the mucosa, enabling the body to absorb their nutrients. Segmentation occurs primarily in the small intestine as food is digested and absorbed. Let's go on a journey through the GI tract, shall we? The process begins with our teeth. We chew food into pieces small enough to swallow. During this process food remains between the teeth and our mouths contain large numbers of bacteria that flourish on the leftover food. During their metabolism these bacteria release acids that can dissolve enamel and create cavities. Huzza. Three pairs of salivary glands in our mouth produce a watery fluid called saliva. The parotid gland lies near the back of the jaw, and the smaller submandibular and sublingual glands are located just below the lower jaw and below the tongue. All three glands connect to the oral cavity via ducts. Saliva moistens food making it easier to chew and swallow. Saliva contains four ingredients, each with an important function. One is mucin, a mucus like protein that holds food particles together so they can be swallowed more easily. An enzyme called salivary amylase begins the process of digesting carbohydrates. Bicarbonate in saliva maintains the pH of the mouth between 6.5 and 7.5, the range over which salivary amylase is most effective. Salivary bicarbonate may also protect your teeth against those pesky acid-producing bacteria. Saliva also contains small amounts of an enzyme called lysozyme that inhibits bacterial growth. After chewing our food and mixing it with saliva, the tongue pushes it into the pharynx or throat for swallowing. Just beyond the pharynx is the esophagus, a muscular tube consisting of both skeletal and smooth muscle that connects the pharynx to the stomach. The lining of the esophagus produces lubricating mucus that helps food slide easily. The presence of a bolus of food in the esophagus initiates peristaltic contractions of the smooth muscle that push things to the stomach. Gravity also assists peristalsis in propelling food. However, peristaltic contractions enable the esophagus to transport food even against gravity, such as when we are lying down. The lower esophageal sphincter, located at the base of the esophagus, opens briefly as food arrives and closes after it passes into the stomach. The sphincter prevents reflux of the stomach's’ contents back into the esophagus. The stomach is a muscular, expandable sac that performs three important functions:
Typically, the stomach produces 1-2 liters of gastric juice per day, most of it immediately after meals. The pepsin and acid in gastric juice dissolve the connective tissue in food and digest proteins and peptides into amino acids so they can be absorbed by the small intestine. The watery mixture of partially digested food and gastric juice that is delivered to the small intestine is called chyme. A protective barrier of mucus lines the stomach and protects it from the gastric juices. It takes two to six hours for the stomach to empty completely after a meal. Most forceful when the stomach is full, peristalsis declines as the stomach empties. Chyme with a high acid or fat content stimulates the release of hormones that slow stomach peristalsis, giving the small intestines time to absorb the nutrients. Between the stomach and the small intestine is the pyloric sphincter, which regulates the rate of transport of chyme into the small intestine. Neat fact: the stomach does not absorb nutrients because it lacks the required cellular transporting mechanisms and its inner lining is coated with mucus. Exceptions to this rule are aspirin and alcohol, both of which are small lipid-soluble substances that can cross the mucus barrier and be absorbed into the bloodstream directly from the stomach. When the stomach contains food, alcohol is absorbed more slowly. The small intestine has two major functions: digestion and absorption! The stomach partially digests proteins and this process continues in the small intestines. Digestion of proteins, carbohydrates, and lipids in the small intestines involves neutralizing the highly acidic gastric juice and adding additional digestive enzymes from the intestine and pancreas. Eventually everything gets broken down to single amino acids, monosaccharides, fatty acids, and glycerol. These are small enough to be transported across mucosal cells into the blood. Approximately 95% of the food you eat is absorbed in the small intestines. The small intestine consists of three different regions. The first region, the duodenum, is where most of the digestion takes place. The products of digestion are absorbed primarily in the other two segments, the jejunum and ileum, which together are about 10 (freakin’) feet long. HUZZZAAA! The structure of the small intestine wall makes it well suited for absorption. The mucosa contains large folds covered with microscopic projections called villi. Each epithelial cell of the villi has dozens of even smaller, cytoplasmic projections called microvilli. The microvilli give the mucosal surface a velvety appearance. These features enlarge the surface area of the small intestine by more than 500 times, increasing its ability to absorb nutrients. Let’s pause on our journey through the digestive system and take a look at the other accessory organs of the digestive tract. We’ve examined how the salivary glands in the mouth, stomach and small intestine function. What are the roles of the liver, pancreas and gallbladder in digestion? The pancreas, an elegant elongated organ that lies just behind the stomach, has both endocrine and exocrine functions. We’ve looked at its endocrine function in a previous post so let’s turn our attention to its exocrine role. This powerhouse organ produces and secretes digestive enzymes and sodium bicarbonate. Two pancreatic ducts deliver these secretions to the duodenum, where they facilitate the process of digestion. Neat! The liver is a large organ located in the upper right abdominal cavity. The liver performs many significant functions, some of which are associated with digestion. In terms of digestion, the liver’s primary function is to facilitate the digestion and absorption of lipids of producing bile. Bile is a luscious, watery mixture containing electrolytes, cholesterol, bile salts (yummy), a phospho-lipid, and pigments derived from the breakdown of hemoglobin. In addition the liver serves a number of other functions that maintain allostasis. The liver:
Because of its central role in so many different functions, liver injury can be particularly dangerous. Overexposure to toxic chemicals, medications or alcohol can damage the liver because it takes up these substances to “detoxify” them, killing some liver cells in the process. Finally, the bile produced by the liver flows through ducts to the gallbladder. The gallbladder concentrates the bile by removing most of the water and stores it until after a meal, when it is secreted into the small intestine via the bile duct, which joins the pancreatic duct. Okay- back to our journey! By the time the contents of the digestive tract reach the large intestine, most nutrients have been absorbed. The large intestine absorbs the last of the remaining water, ions and nutrients and stores the now nearly solid waste material until can be eliminated. This gal is larger in diameter than the small intestine but shorter in length (roughly 5 feet). The large intestine begins at a pouch called the cecum, which receives the cyme from the small intestine. A small fingerlike pouch, the appendix, extends from the cecum. From the cecum, the large intestine continues as the colon which joins the rectum, the passageway through which the waste materials, now called feces, pass as they are eliminated through the anus. Yahoooo! We made it. Okay, but… how are nutrients absorbed? Once food has been digested, how does your body absorb the nutrients? The mechanism depends on the type of nutrient. -Proteins and carbohydrates are absorbed from the lumen of the small intestine by active transport processes, then move by facilitated diffusion into capillaries. The components of lipid digestion are transported to the mucosa in micelles, diffuse into the cells, and recombine into lipids within the cells. Then they are coated with protein to become chylomicrons that enter the lymph. -The digestive system also absorbs water, vitamins, minerals and digestive secretions. Herbal musings
An out-of-balance gut is no fun. Indigestion, gas, heartburn, ulcers, bowel irregularity and deterioration of the gut can be painful, debilitating and at times life threatening. Thankfully, the gut responds quickly and happily to herbal therapies and diet changes that can heal damage and retrain function while resolving symptoms, supporting health and bringing balance to the entire system. One of my favorite categories of herbs are the bitters! Bitters single handedly turn on your GI tract while also benefiting liver function and detoxification. Bitters can help with a lot of issues from modulating weak or excessive appetite and weight to aiding sluggish digestion and elimination, constipation, indigestion, excess fullness, poor nutrient absorption and high cholesterol. Some great bitters include artichoke leaf, dandelion leaf and root, burdock, turmeric, ginger, schizandra, and citrus peel. Additionally there are a number of soothing, gut-healing herbs that help resolve gastric inflammation and other gut issues. My go-to gut soothing herbs are licorice root and marshmallow root. Other gut healing herbs include plantain, calendula, gotu kola and chickweed (best fresh), all of which you can incorporate daily into tea blends, soup broth, pesto or other kinds of food. These plants soothe inflamed tissue and promote wound-healing process. They're better known as topical wound healers but it's the same concept. Gosh, I could go on about herbs for the GI tract so I'll conclude by saying that gas, pain and bloating can be soothed by fennel and peppermint. Final thoughts: watch out for food allergies and... CHEW YOUR FOOD! xoxoxo ![]() The world is full of living organisms too small to be seen with the naked eye. Called microorganisms or microbes, these tiny critters can be found on doorknobs, our skin, car keys, and almost everything around us. They’re in the soil in our backyard, on the food we eat, and in the air. Most are harmless and some are extremely beneficial. Only a few cause disease, but they account for many disorders and contribute to human suffering worldwide. These challenges that are part of our world come from outside the body, but others come from within. Abnormal cells can develop due to inherited factors, environmental pollutants and many other reasons- some of which are unknown to us. Although we still have much to learn about what causes cells to become abnormal, we do know that our bodies dispatch many of them before they can develop into things like cancer. With all the microbes, environmental toxins and other stuff hanging around, why aren’t we constantly ill? …. (crickets)..... For this we can thank our bodies luscious and glorious defense mechanism system, which detects and wards off many of these threats before they have a chance to do us real harm. These mechanisms include physical and chemical barriers that prevent many harmful substances from entering the body (such as skin and stomach acid), nonspecific mechanisms that help the body respond to all kinds of tissue damage and specific defense mechanisms that recognize and kill particular microorganisms and abnormal cells (such as specific immune responses). All these mechanisms work cooperatively and simultaneously to protect us. They involve a wide variety of cells, proteins, chemicals and organs. The lymphatic system (Ta- DA!) plays a crucial role and in this blog post we will look at its function. These mechanisms also involve the immune system, a complex group of cells, proteins, and structures of the lymphatic and circulatory systems. The lymphatic system is closely associated with the cardiovascular system. The lymphatic system performs three important functions:
The lymphatic system helps to maintain blood volume and interstitial fluid volume by returning excess fluid that has been filtered out of the capillaries back to the cardiovascular system. Let’s take a look at how these various systems protect us from disease and injury. The above picture shows the structure of the lymphatic system. The lymphatic system begins as a network of small, blind-ended lymphatic capillaries in the vicinity of the cells and blood capillaries. The fluid in the lymphatic capillaries is lymph, a milky body fluid that contains white blood cells, proteins, fats and the occasional bacterium. The lymph is formed when the interstitial fluid (the fluid which lies in the interstices of all body tissues) is collected through lymph capillaries. Lymphatic capillaries merge to form the lymphatic vessels. Located at intervals along the lymphatic vessels are small organs called lymph nodes. Lymph nodes remove microorganisms, cellular debris, and abnormal cells from the lymph before returning it to the cardiovascular system. There are hundreds of lymph nodes clustered in the areas of the digestive tract, neck, armpits and groin. The lymphatic vessels carry lymph into and out of each node. Valves within these vessels ensure that lymph flows only in one direction. As the fluid flows through a node, the macrophages destroy foreign cells by phagocytosis, and the lymphocytes activate other defense mechanisms. The cleansed lymph fluid flows out of the node and continues on its path to the veins. The immune system is typically divided into two categories - innate and adaptive- although these distinctions are not mutually exclusive. Innate immunity refers to nonspecific defense mechanisms that come into play immediately or within hours of an antigen’s appearance in the body. These mechanisms include physical barriers such as skin, chemicals in the blood and immune system cells that attack foreign cells in the body. The innate immune response is activated by chemical properties of the antigen. Adaptive immunity refers to antigen-specific immune response. The adaptive immune response is more complex than the innate. The antigen must first be processed and recognized. Once an antigen has been recognized, the adaptive immune system creates an army of immune cells that are specifically designed to attack that antigen. Adaptive immunity also includes a “memory” that makes future responses against a specific antigen more efficient. There are two types of adaptive immune responses: humoral immunity, mediated by antibodies produced by B lymphocytes, and cell-mediated immunity, mediated by T lymphocytes. Humoral and cell-mediated immunity are together responsible for coping with foreign bodies like viruses and bacteria that enter a human organism and cause various diseases. In the adaptive immune system, humoral immunity is responsible for viruses and bacteria that have not yet penetrated into the cell. The cells that make humoral immunity possible are known as b-cells, which contain b-lymphocytes. In the adaptive immune system, cell-mediated immunity is responsible for viruses and bacteria that have penetrated into the cell. The cells that make cell-mediated immunity possible are known as t-cells, which mature in the thymus. Overall, humoral immunity is an aspect of immunity that is mediated by macromolecules found in extracellular fluids such as secreted antibodies, complement proteins, and certain antimicrobial peptides. Humoral immunity is so named because it involves substances found in the humors or body fluids. The humoral immune response begins with the recognition of antigens by naive B cells. These cells then undergo a process of clonal expansion and differentiation. Through this process, the B cell matures into antibody secreting plasma cells, which secrete antibodies. Antibodies are proteins that bind with and neutralize specific antigens (any substance that mobilizes the immune system and provokes an immune response). B cells release antibodies into the lymph, bloodstream, and tissue fluid, where they circulate throughout the body. Antibody-mediated immunity works best against viruses, bacteria, and foreign molecules that are soluble in blood and lymph. The T-cells responsible for cell-mediated immunity develop from stem cells in bone marrow but mature in the thymus gland. T-cells directly attack foreign cells that carry antigens, or release substances that enhance the immune response. When a T-cell with CD4 receptors encounters an APC displaying an antigen-MHC complex, it differentiates into a helper T-cell. Helper T-cell do not directly kill infected cells, as cytotoxic T-cells do. Instead they help activate cytotoxic T-cells and macrophages to attack infected cells or they stimulate B-cells to secrete antibodies. The role of the helper T-cell is crucial. Without them the entire immune response would be severely impaired or nonexistent because they direct or enhance the activities of so many other cells in the immune system. The regulatory T-cells (formerly known as suppressor T-cells in one of the texts book I’m perusing) are a subpopulation of T-cells which modulate the immune system, maintain tolerance to self-antigens, and prevent autoimmune disease. Finally, cytotoxic T-cells kill abnormal and foreign cells. When a mature T-cell with a CD8 receptors meets an APC that displays an antigen-MHC complex, it is activated to produce a clone of cytotoxic T-cells, also called (MY FAVORITE) killer T-cells or T8s. These are the only T-cells that directly attack and destroy other cells. Once activated, these killers roam through the body. They circulate through blood, lymph, and lymphatic tissues in search of cells that display the antigens they recognize. They migrate to a tumor or site of infection, where they release chemicals that are toxic to abnormal cells. Ugh- so sweet Herbal medicine can help in tending to your inner army...
From strengthening and modulating the immune system with medicinal mushrooms and plants like astragalus, codonopsis, and elder to treating common infections with echinacea and the garden-variety antimicrobials such as oregano, thyme and bee balm, there is SO MUCH in the realm of plant medicine to assist humans in tending our inner army. ![]() The Cardiovascular System (sometimes called the circulatory system) consists of the heart, blood vessels, and lymphatics. The heart provides the power to move the blood and the vascular system represents the network of branching conduit vessels through which the blood flows. This network brings life-sustaining oxygen and nutrients to the body's cells, removes metabolic waste products, and carries hormones from one part of the body to the other. Right off the bat, what immediately catches my interest about this system is the heart. On a mechanical level, this mystical love pump is capable of greater reliability than some of the best pumps ever built by humans and can easily withstand 80 to 100 years of continuous service without ever stopping for repairs. Its output is also fully adjustable on demand, over a range of about 5 to 25 liters of blood per minute. On another level, the heart is an important organ of perception. Both recent and ancient wisdom invites us to think of the heart as an organ of sensitive perception and integration. In our therapeutics class on cardiovascular wellness, Betzy spoke about the heart's connection to both our nervous and endocrine systems and its ability to perceive electromagnetic fields (what small people call - vibes) from people, animals, plants and the environment. Betzy compared the cardiovascular system to an internal tree of life, that connects and responds to our external world as well as internal needs. Unfortunately, in our modern life it's challenging to get the same amount of movement and time spent outdoors that our ancestors did. We are a society that predominately lives in our heads rather than our bodies and we are far more sedentary and indoor dwelling and head centered than we evolved to be. Additionally, our culture doesn't support strong community ties, love for the natural world and connection - even to our closest loved ones. When we don't exercise our intuitive faculties or emotional ones either, we start to lose our strength and vitality. It's no wonder that the cardiovascular disease is the most common serious, life-threatening illness we face worldwide. As with any muscle, lack of use leads to deterioration, inflexibility and lack of responsiveness - the opposite of vitality and resilient health. Let's take a closer look at the inner workings of this system to gain some more insight into what it's all about. Blood: Did you know that 7-8% of human body weight is from blood? In adults, this amounts to 4.5-6 quarts of blood. This essential fluid carries out the critical functions of transporting oxygen and nutrients to our cells and getting rid of carbon dioxide, ammonia, and other waste products. In addition, it plays a vital role in our immune system and in maintaining a relatively constant body temperature. Blood is a highly specialized tissue composed of more than 4,000 different kinds of components. Four of the most important ones are red cells, white cells, platelets, and plasma. All humans produce these blood components--there are no populational or regional differences. Red blood cells transport oxygen and carbon dioxide to and from body tissues. They contain hemoglobin, the oxygen carrying substance that gives blood its red color. These cells have an average lifespan of 120 days and are released by bone marrow. White blood cells participate in the body’s defense and immune systems. These five types of cells are classified as granulocytes and agranulocytes. Platelets are small, colorless, disk-shaped cytoplasmic fragments spit from cells in bone marrow. These fragments have a lifespan of about ten days and perform three vital functions which includes initiating contraction of damaged blood vessels to minimize blood loss, forming hemostatic plugs in injured blood vessels and with plasma, providing materials that accelerate blood coagulation. Plasma is the clear, straw-colored liquid portion of blood that remains after red blood cells, white blood cells, platelets and other cellular components are removed. It is the largest component of human blood, comprising about 55 percent, and contains water, salts, enzymes, antibodies and other proteins. The Pulmonary and Systemic Circuits: The above diagram shows the general structure of the entire cardiovascular system. Note that the heart is pumping blood through the lungs (the pulmonary circuit) and through the rest of the body to all the cells (the systemic circuit) simultaneously. Each circuit has its own set of blood vessels. Let’s follow the pulmonary circuit first:
The system circuit serves the rest of the body. When blood enters the left ventricle, it begins the systemic circuit, which takes it to the rest of the body.
Arteries, Arterioles, Capillaries, Venules, and Veins- Who are they? As described in the pulmonary and systemic circuits, when blood leaves the heart it is pumped into large, muscular, thick-walled arteries. Arteries transport blood away from the heart. The larger arteries have a thick layer of muscles because they must be able to withstand the high pressure generated by the heart. Arteries branch again and again, so the farther the blood moves from the heart, the smaller in diameter the arteries become. Eventually the blood reaches the smallest arteries, called arterioles (literally, “little arteries”). The largest artery in the body, the aorta, is about 2.5 centimeters (roughly 1 inch) wide. In contract, arterioles have a diameter of 0.3 millimeter or less, about the width of a piece of thread. By the time blood throws through the arterioles, blood pressure has fallen considerably. Consequently, arterioles can be simpler in structure. Arterioles connect to the smallest blood vessels, called capillaries. Capillaries are thin-walled vessels that average only about one-hundredth of a millimeter in diameter- not much wider than the red blood cells that travel through them. In fact, they are so narrow that red blood cells often have to pass through them in single file or even bend to squeeze through them. From the capillaries, blood flows back to the heart through venules (small veins) and veins. LIke the walls of arteries, the walls of veins consist of three layers of tissue. However, the outer two layers of the walls of veins are much thinner than those of arteries. Veins also have a larger lumen (are larger in diameter) than arteries. The anatomical differences between arteries and veins reflect their functional differences. As blood moves through the cardiovascular system, the blood pressure becomes lower and lower. The pressure in veins is only a small fracture of the pressure in arteries, so veins do not need nearly as much wall strength (provided by muscle and connective tissue) as arteries. In addition to their transport function, veins serve as a blood volume reservoir for the entire cardiovascular system. Nearly two-thirds of all the blood in your body is in your veins. Very cool! The Hepatic Portal System The hepatic portal system is the system of veins comprising the hepatic portal vein and its tributaries. This system is responsible for directing blood from parts of the gastrointestinal tract to the liver. Substances absorbed in the small intensive travel first to the liver for processing before continuing to the heart. Not all of the gastrointestinal tract is part of this system but overall it extends from about the lower portion of the esophagus to the upper part of the anal canal. It also includes venous drainage from the spleen and pancreas. Blood pressure is the force that blood exerts on the wall of a blood vessel as a result of the pumping action of the heart. Blood pressure is not the same in all blood vessels (or people for that matter - like this bizarre dude in the picture above). heh. When health professionals measure your blood pressure they are assessing only the pressure in your main arteries. From a clinical standpoint, blood pressure gives valuable clues about the relative volume of blood in the vessels, the condition or stiffness of the arteries, and the overall efficiency of the cardiovascular system. Trends in blood pressure over time are a useful indicator of cardiovascular health. Blood pressure higher than normal is called hypertension and is a significant risk factor for cardiovascular disease. The greater pressure, the greater the strain on the cardiovascular system. Blood vessels react to the pounding by becoming hardened and scarred, which makes them less able to stretch during systole. Hypertension also places a greater strain on the heart, because the work it must do is directly proportional to the arterial pressure against which it must pump. Smoking, a sedentary lifestyle, obesity, heredity, persistent emotional stress, heavy alcohol consumption and other factors can increase the risk of hypertension. How this all relates to Herbal Medicine:
As with so many aspects of human health, the basic approach to both prevention and management of cardiovascular issues or disease is undertaking appropriate exercise, mind-body balance, and diet - with herbs to support more specific aspects of health health, as needed. Regular cardio exercise strengthens the function of the heart while meditation, breathwork and exercises with a mind-body component like yoga and tai chi have been shown to reduce heart-damaging stress and slow or even reverse heart disease. Heart tonics with plants like rose, hawthorn, rooibos, hibiscus, linden and cacao have all been shown to be beneficial, with broad-reaching cardiovascular benefits. A heart healthy diet full of berries, leafy greens and vegetables is a powerful component of strong cardiovascular health. Remember kids, it's never too late to: I’m running on a trail in a nature reserve outside of Montpelier after a long day working on my feet. My stomach rumbles with hunger and my lips feel parched from not drinking enough water. There’s a strong breeze in the air and I have goose bumps on my arm as my body hasn’t warmed up to the jogging yet. As I come around a turn in the trail, I hear a tree cracking above my head that distracts my attention. I look up to see what made the sound and then slip on a rock and start to fall forward. My body responds by recoiling and I slide and catch my fall by landing on my feet and hustling out of the way of a large branch falling from the tree above. Whhhattttt a system! My nervous system has my back. It's a dynamic, split-second acting, brilliant living presence within me that is constantly receiving input from all kinds of sources and sorting through large amounts of information on a moment to moment basis, including data stored in my memory banks about the meaning of these sounds and sensations and other stimuli. My luscious nervous system integrates this seemingly unrelated information quickly and this allows me to react in time. Let’s take a look at this extraordinary part of our body. The nervous system receives information from our senses. Then it integrates the different pieces of information from many different sources and makes sense of it as a whole. Instantaneously it sifts through mountains of data and comes up with a plan or course of action. What’s so fascinating to me is that all this is going on automatically without requiring my attention or even my conscious decision making. However, the nervous system can bring selected information to the level of my conscious awareness. In conjunction with the endocrine system, the nervous system works to support allostasis and allows us to feel emotions, be aware of ourselves and exert conscious control over the extraordinary diversity of our physical movements and experiences. The nervous system consists of the central nervous system and the peripheral nervous system. The central nervous system consists of the brain and the spinal cord. This system receives, processes, stores and transfers information. The peripheral nervous system represents components of the nervous system that lie outside the central nervous system. See picture below. The peripheral nervous system has two functional subdivisions: the sensory division of the peripheral nervous system (see yellow side of diagram) carries information to the brain and spinal cord and the motor division (see purple side of diagram) carries information from the central nervous system. The motor division of the peripheral nervous system is further subdivided as you can see in the diagram above. The somatic division controls skeletal muscles while the autonomic division controls smooth muscles, cardiac muscles and glands. Additionally, the autonomic division has two subdivisions called the sympathetic and parasympathetic divisions. These two parts work antagonistically to slow us down to rest and digest or fire us up to accomplish our mission in the world or escape from a falling tree. While the sympathetic and parasympathetic oppose each other, they essentially work together to accomplish the automatic, subconscious goal of allostasis. The sympathetic division of the autonomic nervous system arouses the body. Preganglionic motor neurons of the sympathetic division originate in the thoracic and lumbar regions of the spinal cord. Many of them attach to a chain of sympathetic ganglia that lie alongside the spinal cord. Because the sympathetic division is are well connected to each other, the sympathetic division tends to produce a unified response in all organs at once, transmitting signals that prepare the body for emergencies and situations requiring high levels of mental alertness or physical activity. This could include fighting or running away from danger (“flight or fight”) and even play or sexual activity. The sympathetic division is in charge of increasing heart rate and respiration, raising blood pressure, dilating the pupils and other effects that help you detect and respond quickly to changes in your environment. In addition, the sympathetic division also reduces blood flow to organs that do not help you cope with an immediate emergency, such as the intestines and kidneys and this division inhibits less important body functions such as digestion and production of saliva. This is why it’s common to get a dry mouth during highly stressful moments. See my drawing below for a visual of the divisions of the autonomic nervous system. The parasympathetic division predominates during relaxation. Preganglionic neurons of this division originate either in the brain or from the sacral region of the spinal cord. The ganglia where the preganglionic neurons synapse with the postganglionic neurons is generally some distance from the central nervous system and may even be in the target organ itself. The parasympathetic division predominates in situations in which one is relaxed. This division transmits signals that lower heart rate and respiration, increase digestion, permit defecation and urination, and exerts calming, restorative effects that counteract the fight or flight stimulation of the sympathetic division. Curiously, parasympathetic nerves are also responsible for the vasodilation that causes erections in the penis and swelling of the labia and erection of the clitoris in the vagina. Overall, it appears that the actions of the sympathetic and parasympathetic divisions oppose each other work. But their seemingly antagonistic actions work together to accomplish the automatic, subconscious maintenance of allostasis. Both systems are intimately involved in the feedback loops that help to make allostasis happen. As we’ve looked at, the nervous system coordinates all body functions, enabling a person to adapt to changes in internal and external environments and thus maintain allostasis. This system has two main types of cells - neurons, that act as conducting cells and neuroglia, that act as supporting cells. Our dear neuron is the basic unit of the nervous system. This highly skilled and specialized conductor cell receives and transmits electrochemical nerve impulses. Let’s take a look at the various parts of this mystical unit. Axons and dendrites are threadlike nerve fibers that extend from the central cell body and transmit signals. In particular, the axons conduct nerve impulses away from cell bodies and are covered in a white, fatty segmented covering called a myelin sheath. Dendrites on the other hand are short, thick, branched extensions of the cell body that receive impulses from other cells and conduct information on toward the cell body. Neurons receive information in the form of electrochemical information from other neurons at the cell body. If the incoming information is of the right kind and is strong enough, the neuron responds by generating an electrical impulse of its own where the dendrite joins the axon. The impulse is then transmitted from one end of the axon to the other, bypassing the cell body. The impulse stimulates synaptic vesicles in the presynaptic axon terminal. A neurotransmitter substance is released and diffuses to bind to specific receptors. This stimulates or inhibits stimulation of the postsynaptic neuron. The reflex arc is the transmission of sensory impulses to a motor neuron via the dorsal root. The motor neuron delivers the impulse to where it needs to go - a muscle or gland, which then produces an immediate response. All this happens in an instant. Incredible! Reflection:
Because the nervous system is so complex and controls so many bodily functions, disorders of the nervous system can be particularly debilitating. Trauma, infections, and brain tumors can cause major injury as well as disorders of neural and synaptic transmission like Parkinson’s disease, a progressive, degenerative disorder that strikes nearly 50,000 people a year in North America, most over age 55. Symptoms include stiff joints and muscle tremors in the hands and feet. Eventually people with Parkinson’s lose mobility; they may also become mentally impaired. My father died this past November after battling this disease for nine years. It was a grueling and devastating decline and it's been hard but interesting to read more about it during this unit. Parkinson's is caused by the degeneration of dopamine-releasing neurons in the area of the midbrain that coordinates muscle movement. The shortage of dopamine impairs the ability to perform smooth, coordinated motions. My father was prescribed L-dopa, a drug that the body converts into dopamine, but this does not slow the loss of neurons. Even taking the medication for years my father rapidly lost his ability to feed himself, walk and eventually talk. It was heart breaking to watch him want to do things but his body wouldn’t respond. I could almost see the lack of electrical impulse. Watching my father suffer for so long and feeling powerless to do anything about it is one of the reasons I decided to delve deeper into my interest in and love for herbal medicine. I wish I had known that American Skullcap could have eased his symptoms and that there are many other herbs that support the neural brain forest that is rich with memories, emotions, dreams and desires not to mention all the control center systems that I mentioned previously. Our brain controls how we see the world, taste our food, hear music, smell aromas and absorb the wonder of the earth around us. The brain and nervous system ecosystem should not be taken for granted. As we discussed before, neurotransmitters are the substances responsible for transmitting electrical impulses across the neural synapses. When their job is done, enzymes break down the neurotransmitters. Reuptake inhibitors (including the well-known antidepressant selective serotonin reuptake inhibitors SSRIs) inhibit the breakdown of specific neurotransmitters so that more of those neurotransmitters will be present in the body. Neurotransmitters do a wide range of things, and an excess or deficiency of them plays a role in many different diseases. Acetylcholine (ACh) is a major transmitter for basic body functions including contraction and control of muscles. Low ACh levels are associated with Alzheimer’s, dementia and Parkinson’s. I was delighted to discover many of our mint-family brain-boosting herbs like sage, rosemary, lemon balm, and mint for example boost ACh levels by inhibiting the enzyme that breaks it down. I also strongly believe that diet, lifestyle and well-being have an even greater effect as the foundations of health and vitality when it comes to brain health. My father spent a lot of his life extremely stressed out. He also ate very poorly and didn’t exercise and often felt distant from his family and community. Quality food, exercise, community, meditation - these are all important ways to support ourselves on so many levels including strong brain health. Additionally, our brain requires voluminous blood flow to function properly. Blood delivers essential nutrients, including oxygen and glucose, shuttles out our waste and transports hormones. Oxidation and inflammation in the body inhibit blood flow and create blockages in the neural roadways. Some damage may not become obvious until one’s later years, as issues can take decades to accumulate. Herbalism offers us an alternative to the anti-inflammatory drugs so commonly prescribed as well as eating quality food, keeping stress levels down, getting enough sleep and exercise. Other herbs to consider: Indians have revered Gotu Kola as a memory and brain tonic for at least 2,500 years and Ginkgo, turmeric, berries (especially blueberries) and green tea have all been revered for their antioxidant ways. Bacopa (the Ayurvedic creeping water plant) promotes memory and focus and holy basil, ashwagandha, reishi, lemon balm and rhodiola have all been renowned for their antistress, adaptogenic effects. I was having such a hard time caring for myself while caring for my father when he was sick that it was really challenging for me to begin bringing in herbal remedies for him. I try not to be hard on myself about the things I could have done and how much more I could have been there for him. I did the best I could. I feel grateful to have been by his side the last few days of his life, spritzing rose water on his face, swabbing his mouth with fresh water and relighting the sage smudge in the corner of the room - small but potent forms of love medicine offerings. Perhaps someday I’ll be able to offer some herbs to others struggling with similarly demonic nervous system disorders. Ufffffff. Circadian rhythms are physical, mental and behavioral changes that occur based on a 24 hour cycle. This cycle is attuned primarily to light and darkness in a organism's environment and are found in most living things, including animals, plants and many tiny microbes. The "master clock" that controls circadian rhythms consists of a group of nerve cells in the brain called the suprachiasmatic nucleus, or SCN. The SCN contains about 20,000 nerve cells and is located in the hypothalamus, an area of the brain just above where the optic nerves from the eyes cross. Circadian rhythms are important in determining human sleep patterns. The body's master clock, or SCN, controls the production of melatonin, a hormone that makes you sleepy. Since it is located just above the optic nerves, which relay information from the eyes to the brain, the SCN receives information about incoming light. When there is less light—like at night—the SCN tells the brain to make more melatonin so you get drowsy. Circadian rhythms can influence sleep-wake cycles, hormone release, body temperature and other important bodily functions. They have been linked to various sleep disorders, such as insomnia. Abnormal circadian rhythms have also been associated with obesity, diabetes, depression, bipolar disorder and seasonal affective disorder. Lifestyle and herbal musings: Stress is a major factor in disruption of sleep and the production of melatonin. There are sedative herbs at night or stress-relieving herbs that can be taken during the day that can help but it's important to try to reduce the stressor directly. Sometimes one's life situation can't be changed and thus finding more relaxing time for oneself can be crucial - meditation, yoga, daytime exercise, or an evening wind-down ritual of reading and sipping tea can really help. Stimulants can make some people restless and more apt to wake up during the night or struggle to fall asleep. Coffee, chocolate, yerba mate, soda and tea are obvious late-night no-nos. There are other remedies that don't contain caffeine that can be overly simulating, such as B vitamins, stimulant adaptogens, blood pressure medications, antidepressants, dementia medications, antihistamines, glucosamines, and statins. Alcohol can initially sedate but ultimately prevents deep sleep. Late-night eating can wreak havoc on a good night's sleep, especially when digestion and liver involvement kick in a few hours after you eat. Try to stop eating at least four hours before bedtime and avoid large, heavy, fatty, sugary meals in the evening. Exercise, unplugging before bed and developing a sleep ritual are all great ways to improve one's sleep. Some herbal sleep aids include valerian, california poppy, skullcap, passionflower, chamomile, hops, blue vervain, wood betony and wild lettuce. The endocrine system is a collection of specialized cells, tissues, and glands that produce and secrete circulating chemical messenger molecules called hormones. Most hormones are secreted by endocrine glands - ductless organs that secrete their products into interstitial fluid, lymph, and blood. Hormones are bloodborne units of information, just as nerve impulses are units of information carried in nerves. Some hormones participate in feedback control loops regulating various bodily functions. We need these hormones to maintain allostasis. Other hormones produce specific effects, such as contractions of the uterus during childbirth, growth during childhood and the exciting development of sexual characteristics at puberty. We need specific hormones to be able to carry out each of these very specific functions. The endocrine system differs from the nervous system in that hormones of the endocrine system reach nearly every living cell (through circulation in the blood), each hormone acts only on certain cells (with target cells that have the appropriate receptor) and endocrine control tends to be slower than nervous system control. Due to these differences it’s understandable why the reflexes that prompt us to avoid a hot surface are controlled by the nervous system and that endocrine communication is highly effective for longer-term controls such as regulating blood pressure or the production of red blood cells. Hormones are generally classified into two basic categories based on their structure and mechanism of action: Steroid hormones are structurally related to cholesterol. They are all synthesized from cholesterol and all are lipid soluble. Nonsteroid hormones consist of, or at least partly derived from the amino acid building blocks of protein. In general, they are water soluble. The differences in lipid solubility explain most of the important differences in how the two categories of hormones work. Steroid hormones usually enter the cell, bind to an intracellular receptor and activate genes that produce new proteins. Nonsteroid hormones generally bind to receptors on the cell’s surface. Their binding either opens or closes cell membrane ion channels or activates enzymes within the cell. Negative and Positive Feedback Loops Feedback loops can enhance or buffer changes that occur in a system. Positive feedback loops enhance or amplify changes, this tends to move a system away from its equilibrium state and make it more unstable. Negative feedbacks tend to dampen or buffer changes; this tends to hold a system to some equilibrium state making it more stable. As messenger molecules, some hormones participate in internal allostatic control mechanisms and control vital physiological processes. It is essential to regulate carefully the rate at which each hormone is secreted so that its concentration in blood is just right to carry out its intended function. In a negative feedback loop involving a hormone, the endocrine gland is the control center and the hormone represents the pathway between the control center and the hormone’s target cells, tissues or organs. A negative feedback loop involving an endocrine gland and a hormone is a stable, self-adjusting mechanism for maintaining homeostasis of the controlled variable, because any change in the controlled variable sets in motion a response that reverses that change. Not all negative feedback loops are as simple as the one I described. In some cases the real control center is the brain, which activates an endocrine gland via nerves. The effect is the same. Additionally, a few hormones are secreted in response to specific environmental cues or for particular purposes such as puberty. This type of secretion is not part of a negative feedback loop. The pituitary gland- is a small endocrine gland located beneath the hypothalamus and connected to it by a stalk of tissue. The hypothalamus also produces hormones and monitors the pituitary gland. The pituitary gland is sometimes called “the master gland” because it secretes eight different hormones and regulates many of the other endocrine glands. The hypothalamus creates neuron cell bodies that make either antidiuretic hormones (ADH) or oxytocin - both nonsteroid hormones - and then sends the hormones down the axon for storage endings in the pituitary. ADH acts on the kidneys to regulate water balance and oxytocin causes uterine contractions and milk ejection in pregnant and lactating women. In both sexes, oxytocin contributes to feelings of sexual satisfaction. The anterior pituitary produces six key hormones:
Thyroid - The thyroid and parathyroid glands are anatomically linked. The thyroid gland is situated just below the larynx at the front of the trachea and the two lobes of the thyroid gland wrap part of the way around the trachea. The four small parathyroid glands are embedded in the back of the thyroid. The thyroid and parathyroid glands are both functionally linked- they help regulate calcium balance. In addition, the thyroid has a separate and important role in controlling metabolism. The thyroid gland produces two very similar hormones called thyroxine (T4) and triiodothyronine (T3). They’re identical except that thyroxine contains four molecules of iodine whereas T3 contains only three. The thyroid gland secretes mainly thyroxine but eventually most of it is converted to the more active T3 form of the hormone in the blood. These thyroid hormones regulate metabolism. Calcitonin, the other main hormone of the thyroid gland is produced by a separate group of thyroid cells. Calcitonin decreases the rate of bone resorption by inhibiting the activity of osteoclasts. It also stimulates the uptake of calcium by bone. The parathyroid glands produce only one hormone, parathyroid hormone which removes calcium and phosphate from bone, increases absorption of calcium by the digestive tract and causes the kidneys to retain calcium and excrete phosphate. Adrenal Glands- are two small endocrine organs located just above the kidneys. Each gland has an outer layer, the adrenal cortex, and an inner core, the adrenal medulla. The adrenal cortex produces small amounts of the sex hormones estrogen and testosterone and two classes of steroid hormones called glucocorticoids and mineralocorticoids. The adrenal cortex produces a group of glucocorticoids with nearly identical structures. Cortisol accounts for approximately 95% of these glucocorticoids. The other hormones produced by the adrenal cortex are the mineralocorticoids, the most abundant of which is aldosterone. The adrenal medulla produces nonsteroid hormones epinephrine (adrenaline) and norepinephrine (noradrenaline). These hormones play roles in metabolism and controlling blood pressure and heart activity. Pineal - The pineal gland is a pea-sized gland located deep within the brain, in the roof of the third ventricle. Its name derives from the fact that it is shaped like a small pine cone (hehe). More than 200 million years ago our pineal gland was photosensitive area or “third eye” located near the skin’s surface. Although it is now shielded from the sun by our thick skull, it still retains its photosensitivity because it receives input directly from the eyes via the optic nerve and nerve pathways in the brain. The pineal gland secretes the hormone melatonin in a cyclic manner coupled to the daily cycle of light and dark. Melatonin is sometimes called the “hormone of darkness” because its rate of secretion rises nearly 10 fold at night and then falls again during the daylight. Its secretion appears to be regulated by the absence or presence of visual cues. During the day, nerve impulses from the retina inhibit its release. AND we are just beginning to understand what melatonin does… Notes on the role of the pancreatic endocrine cells in the regulation of blood glucose: Within the pancreas, clusters of cells called the pancreatic islets produce and secret three hormones - glucagon, insulin, and somatostatin. Glucagon raises blood glucose levels, insulin lowers blood glucose levels, and somatostatin appears to inhibit the secretion of glucagon and insulin. Overall thoughts on the Endocrine System and its connection to Herbal Medicine: I’m fascinated by the thyroid. This organ plays an important role in determining our body temperature; the way we digest, metabolize and assimilate food; our body’s ability to make good-quality connective tissue, hair, skin and nails; and our mood. Thyroid fluctuations can affect many things including menopausal symptoms, fertility, and overall vitality. Your body can tilt towards hypothyroidism (underactive/low thyroid) or hyperthyroidism (overactive/high thyroid). Hypothyroidism is the most common thyroid imbalance in which things slow to nearly a halt resulting in colder body temperatures, weight gain, depression, sluggishness, poor digestion, brain fog, hair loss, dull skin, and horizontal ridges in the fingernails, among other things. It can look like anemia. Hyperthyroidism is characterized by an overdrive - you might feel like a hot furnace, become rail-thin, toss and turn at night, and feel extremely agitated and anxious. It wears on the whole body and can even make your eyes bug out in advance cases. Even though more and more people - particularly women - have thyroid imbalances, it’s hard to find good information about how to take care of the thyroid holistically. It’s important to get a full thyroid panel completed if you suspect issues. This will give you a better idea of what’s going on as well as rule out issues like anemia and lyme disease. Knowing exactly where you stand can help drive appropriate therapies. Herbal and lifestyle approaches to thyroid issues excel at addressing imbalances and are less apt to have negative side effects like some of the thyroid-focused supplements and pharmaceuticals. Also many underlying causes of thyroid problems relate to stress, grief, autoimmune disease, diet, a sedentary lifestyle, toxins and and emotional connections - consider the possible aggravating factors. Herbs that assist hypothyroid issues are iodine, kelp, selenium, ashwagandha, bacopa and guggul, and tyrosine. Avoid eating excessive amounts if you tend toward hyperthyroid disease. Lemon balm, motherwort and bugleweed are frequently used for hyperthyroid disease. Preliminary research suggests that these herbs inhibit parathyroid functions through a variety of mechanisms including binding to TSH receptors, inhibiting thyroid hormone production and preventing thyroid hormone conversion from T4 to T3. It’s interesting to me that lemon balm and motherwort are commonly used for conditions similar to hyperthyroid disease: insomnia, anxiety, agitation and stress-related cardiac overdrive including panic attacks and palpitations. Vitamin B, magnesium and bitters tend to be beneficial for healthy thyroid function regardless of whether your thyroid needs a boost or needs to be taken down a notch.
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AuthorThe adventures, studies, and musings of a student at the Vermont Center for Integrative Herbalism.
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