2 What is the system? Made up of glands that produce and secrete hormones (chemical messengers) Regulation of growth, metabolism, sexual development Responses to stress and injury Internal balance of body systems (homeostasis) Major Glands 1. Hypothalamus 2. Pituitary 3. Thyroid 4. Parathyroid 5. Adrenals 6. Pineal Body 7. Reproductive organs (ovaries and testes 8. Pancreas endocrine *HORMONES are chemical messengers that act on TARGET CELLS Exocrine Glands – secrete outside the body through ducts and tubes (sweat)
3 Major Glands 1. Hypothalamus 2. Pituitary 3. Thyroid 4. Parathyroid5. Adrenals 6. Pineal Body 7. Reproductive organs (ovaries and testes) 8. Pancreas
4 BIG IDEA HORMONES are chemical MESSENGERS that act on target cells (or organs) Endocrine – secretions inside the body Exocrine – secretions outside the body (sweat) cAMP breaks down glycogen pg. 267
5 Major Structures
6 FQ: How are hormones regulated in the human body?
7 Hormone Action Steroids(cholesterols) – membrane soluableNon steroid hormones – secondary messangers Prostaglandins - act locally, on nearby organs Steroids – (fats/cholesterols) insoluble in water, carried in the blood and released near the vicinity of the target cell (sex hormones and those made by the adrenal glands like cortisol/hydrocortisone and epinephrine) 1. cortisol release from the adrenal gland is controlled by the hypothalamus which signals the anterior pituitary to send a message to the adrenal glands. It aids in the metabolism of fat, sugars, and increases blood sugar 2. epinephrine – fight or flight works on cells to give you energy to get through whatever the situation is Nonsteroid hormones – binding site, activity site (cyclic AMP, cAMP = secondary messenger) – Cannot penetrate the cell wall because they are not fats/cholesterols so they have a binding site – basically there is a receptor that signals the secondary messenger to be made (cAMP from ATP) and then that secondary messenger tells the cell to do something. Prostaglandins – act locally, affecting only the organ where they are produces: They control processes such as inflammation, blood flow, the formation of blood clots and the induction of labor. They are made by a chemical reaction at the site where they are needed and can be made in nearly all the organs in the body.
8 Hormone Control The pituitary is often called the “master gland”Its actions are controlled by the hypothalamus in the brain.
9 Pituitary Gland 22 = Thalamus 24 = Hypothalamus
10 Control of Hormones Negative feedback systemWhen the hormone levels rise, the organ that secretes the hormone is switched off
12 Hormone Path in the “Let Down” response during breast feeding
13 It can affect fat distribution in the body.Growth hormone or GH - GH stimulates growth in childhood and is important for maintaining a healthy body composition. In adults it is also important for maintaining muscle mass and bone mass. It can affect fat distribution in the body. HGH Pathway and Release: The main purpose is its direct effects on a variety of cells within the body. The growth hormone binds to its receptor on target cells, then creates some particular action. Fat cells, for example, are the target cells of HGH, so they have growth hormone receptors. Once bonded there, the growth hormone causes them to break down triglyceride and suppresses their ability to take up and accumulate circulating lipids — in other words, fat storage is prevented! HGH also acts to create other indirect effects in the body by causing secretion of IGF-1, an insulin-like growth factor hormone. IGF-1 is secreted from the liver and other tissues in response to growth hormone. This is the action that governs mostly growth-related effects of HGH. What is meant by “growth”? The obvious answer is, growth means something getting bigger. But don’t be hemmed in by that definition. Growth requires many, many coordinated processes in the body, and that in turn means a complex dance of lots of different hormones, which typically are the messengers that tell different parts of the body what to do and when. Growth hormone indirectly stimulates the synthesis of cartilage cells, resulting in bone growth. This same effect is also the power behind muscle growth. It stimulates both the differentiation and proliferation of muscle cells, stimulates amino acid uptake and synthesizes protein in muscle and other tissues. This is where HGH’s ability to influence overall muscle and skin tone comes from. How about metabolism? Growth hormone has important effects on: Protein metabolism: HGH causes increased amino acid uptake, increased protein synthesis and decreased oxidation of proteins. Fat metabolism: HGH enhances the utilization of fat — gives your body the ability to break down fat cells more efficiently. Carbohydrate metabolism: HGH is one of several hormones that maintain blood sugar within a normal range. Without HGH Because of the abilities of HGH mentioned above, you can soon see that without it, muscle tone declines, fat stubbornly sits in the body and resists metabolism, and hair, skin and nails (all composed of proteins) deteriorate. In fact, scientists now believe that HGH has a role in most healthy functions of the body, including sexual function, proper operation of stomach and bowels, liver, and all glandular systems. Whether HGH is directly interacting with certain cells, or playing its key part in the correct function of other bodily systems, it’s essential throughout the body for youthful vigor and health!
14 That’s a bull of the Belgian Blue breed, which has a genetic anomaly that suppresses the production of a hormone called myostatin that inhibits muscle growth – hence the ‘double muscling’ seen above. Myostatin inhibitor drugs are being developed with the intent of treating muscle-wasting diseases like muscular dystrophy in humans.
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18 Or a person can grow too muchOr a person can grow too much. These are pictures of the man known as “The Alton Giant”, Robert Wadlow. Giantism: excess growth hormone as a child Acromegaly: excess growth hormone as an adult
20 Thyroid-stimulating hormone or TSH - TSH stimulates the thyroid gland to make thyroid hormones, which, in turn, control (regulate) the body's metabolism, energy, growth and development, and nervous system activity.
21 Luteinizing hormone or LH - LH regulates testosterone in men and estrogen in women. (gonadotropin)
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24 Application Activity Choose one of the following hormones. Find an interesting article related to that hormone. It can be about drug interactions, research etc… Growth Hormone, Adrenocorticotropin or ACTH Thyroid Stimulating Hormone, Luteinizing Hormone Follicle Stimulating Hormone - Who wrote it – source - What is the article about: summary of most important parts of the article. - What impact does this information have on humans
25 Posterior Pituitary and the Thyroid
26 Oxytocin - Oxytocin causes milk letdown in nursing mothers and contractions during childbirth.Responsible for sexual arousal, “hard ons,” and ejaculation LH – In males, LH acts upon the Leydig cells of the testis and is regulated by LH.[8] The Leydig cells produce testosterone
27 Pitocin is another very controversial topic in childbearing today.Oxytocin is a natural hormone produced by a woman's body that cause uterine contractions. Pitocin is the synthetic form of oxytocin. Pitocin is generally used in two ways: ) to induce labor, and 2) to augment (speed up) labor.
28 Posterior Pituitary HormonesAntidiuretic hormone or ADH - ADH, also called vasopressin, is stored in the back part of the pituitary gland and regulates water balance. If this hormone is not secreted properly, this can lead to problems of sodium (salt) and water balance, and could also affect the kidneys so that they do not work as well.
29 Diuretics – increase urine production Many common foods and drinks contain chemicals that are diuretics (alcohol) Midol relieves symptoms of bloating because it contains a diuretic that will make you urinate more Active Ingredients: (in each caplet): Acetaminophen (500 mg) (Pain Reliever), Caffeine (60mg) (Diuretic, Stimulant), Pyrilamine Maleate (15 mg) (Diuretic)Inactive Ingredients: Carnauba Wax, Croscarmellose Sodium, FD&C Blue 2, Hypromellose, Magnesium Stearate, Microcrystalline Cellulose, Pregelatinized Starch, Propylene Glycol, Shellac, Titanium Dioxide, Triacetin
30 THYROID GLAND The thyroid hormones control your metabolism, which is the body's ability to break down food and store it as energy and release of energy
31 THYROID HORMONES Thyroxin (T4) & Tri-iodothyronine (T3) - both increase the rate at which cells release energy from carbohydrates Calcitonin – regulates the blood concentration of calcium • BMR – basal metabolic rate : how many calories the body must consume to maintain life BMR Calculator
32 Problems with the ThyroidThyroid hormone is partly made of iodine. Iodine is essential for the formation of thyroxin. If a person doesn’t eat enough iodine, they can’t make thyroid hormone. so the size of the follicle grows • gland grows > GOITER. Iodine is only found in seafood, so if salt wasn’t iodized, a lot of people wouldn’t get enough iodine, and there would be a lot of goiters.
34 Hypothyroidism Before and After TreatmentPuffy face – from water retention which also causes constipation Thyroid hormone underwrites transcription and assembly of glycoaminoglycans. These "water magnets" are building blocks for collagen. Without intracellular glycoaminoglycans, cells can't retain water. Clinically, this manifests as dry, wrinkled skin, lusterless hair, brittle nails and the painful joints of osteoarthritis. Inability to hold water inside cells also results in fluid leakage into extracellular space. This presents as a rounded face, sub-orbital edema, leg edema, and a swollen/scalloped tongue. Thyroid hormone assists insulin in moving glucose from the blood into cells. When thyroid levels are low, more insulin is needed to maintain normal glucose. More insulin means more fat cell hyperplasia, which shows up as increased fat deposition, especially around hips, thighs and abdomen (truncal obesity), all of which point to suboptimal thyroid levels.
35 Cretinism (hypothyroidism in infants)
38 Parathyroid Glands Located behind the thyroid, four tiny glands Parathyroid Hormone (PTH) - takes calcium from the bones to make it available in the blood
39 Adrenal Glands Located at the top of the kidneys Adrenal Cortex - outer area Adrenal Medulla - inner area Adrenal Glands = Adrenaline
41 Adrenal Cortex Aldosterone – a mineralcorticoid, helps kidneys conserve sodium and excrete potassium, maintaining blood pressure Cortisol – glucocortoid, keeps blood glucose levels stable Adrenal Sex Hormones - androgens (male) and estrogens (female) Mineralocorticoids are a class of steroid hormones characterized by their influence on salt and water balances. The primary mineralocorticoid is aldosterone Cortisol is a steroid hormone, more specifically a glucocorticoid, produced by the zona fasciculata of the adrenal cortex.[1] It is released in response to stress and a low level of blood glucocorticoid. Its primary functions are to increase blood sugar through gluconeogenesis, suppress the immune system, and aid with fat, protein, and carbohydrate metabolisms.[2] It also decreases bone formation.[3] Various forms of cortisol are used to treat a variety of diseases. Hydrocortisone (INN, USAN,BAN), which is an identical molecule to cortisol, is one such medication. It can be used to treat people who lack adequate stores of endogenous cortisol
44 How does a stimulus active an endocrine gland? (pg. 268)3 Major Ways: Hormonal: the gland is signaled from another hormone Ex. Thyroid Stimulating hormone triggers thyroid hormones to be produced Humoral: a change in specific ion levels in the blood Not enough ca+ in the blood would triggered parathyroid Neural: when the neurons connected to glands trigger a response Your adrenal glands have neurons that trigger flight or fight so that you can respond to the stimulus quicker
45 Pancreas The pancreas is a large gland behind your stomach that helps the body to maintain healthy blood sugar (glucose) levels. Contains islands of cells called the Islets of Langerhans which secrete glucagon (raises blood glucose) and insulin (lowers blood glucose) Glucagon is a peptide hormone, produced by alpha cells of the pancreas, that raises blood glucose levels. Its effect is opposite that of insulin, which lowers blood glucose levels.[1] The pancreas releases glucagon when blood sugar (glucose) levels fall too low. Glucagon causes the liver to convert stored glycogen into glucose, which is released into the bloodstream. High blood glucose levels stimulate the release of insulin. Insulin allows glucose to be taken up and used by insulin-dependent tissues. Thus, glucagon and insulin are part of a feedback system that keeps blood glucose levels at a stable level.
46 Glucagon – stimulates the liver to break down glycogen, raises blood sugar concentrationInsulin – decreases blood sugar concentrations, affects the uptake of glucose by cells *Both hormones work together to maintain a balance in the blood sugar
47 Diabetes Diabetes Mellitus – results from an insulin deficiency, blood sugar rises (hyperglycemia) and excess is excreted in the urine. Type I - insulin dependent diabetes mellitus or juvenile onset diabetes, often caused by inherited immune disorder that destroys pancreatic cells
49 Type II – mature onset diabetes (usually after the age of 40), often individuals are overweight, can be controlled with diet and exercise Blood sugar test, device pricks the finger and measures the amount of sugar in the blood
51 Diabetes Insipidus Symptoms Excessive thirst ---May be intense or uncontrollable May involve a craving for ice water Excessive urine volume Diabetes insipidus (DI) is an uncommon condition that occurs when the kidneys are unable to conserve water as they perform their function of filtering blood. The amount of water conserved is controlled by antidiuretic hormone (ADH), also called vasopressin. ADH is a hormone produced in a region of the brain called the hypothalamus.
52 Gestational Diabetes Pregnancy hormones can block insulin from doing its job. When this happens, glucose levels may increase in a pregnant woman's blood. Gestational diabetes usually starts halfway through the pregnancy. All pregnant women should receive an oral glucose tolerance test between the 24th and 28th week of pregnancy to screen for the condition.
53 Other Endocrine GlandsPineal Gland – located between the cerebral hemispheres, secretes melatonin, important for maintaining Circadian rhythms (light and dark activity)
54 Location of the Pineal and Pituitary GlandCan you find the hypothalamus?
55 Thymus Gland – large in young children, gradually shrinks with age, secretes thymosins, important to immune function Each T cell attacks a foreign substance which it identifies with its receptor. T cells have receptors which are generated by randomly shuffling gene segments. Each T cell attacks a different antigen.
57 Steroids Anabolic steroids are artificially produced hormones that are the same as, or similar to, androgens, the male-type sex hormones in the body. There are more than 100 variations of anabolic steroids. The most powerful androgen is testosterone.
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