BIOL 252 1st Edition Lecture 14 Outline of Last Lecture I. Modes of ATP Synthesis During ExerciseII. FatigueIII. Classes of Muscle FibersIV. Cardiac MuscleV. Smooth MuscleVI. Intercellular communicationVII. Principles of hormone communicationVIII. Classes of HormonesIX. Hormone Receptors and effectsX. Endocrine disordersXI. Hypothalamus and PituitaryOutline of Current LectureI. PituitaryII. Pineal GlandIII. Thyroid GlandIV. Parathyroid glandsV. Pancreatic IsletsCurrent LectureI. Pituitarya. Posterior Pituitary Hormonesi. ADH (see previous lecture)ii. Oxytocin1. Produced in hypothalamus2. Transported by hypothalamo-hypophyseal tract to posterior lobe3. Neural stimulus => OT => smooth muscle contraction (uterus, reproductive ducts, and mammary glands); promotes emotional bondinga. The “love” hormone4. OT promotes release of milk b. Anterior Pituitary Hormonesi. FSH-follicle stimulating hormoneThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.1. Stimulates secretion of ovarian sex hormones, development of ovarian follicles, and sperm productionii. LH-luteinizing hormoneiii. TSH-thyroid stimulating hormone1. Stimulates secretion of thyroid hormone2. Tropic hormoneiv. ACTH-adrenocorticotropic hormone1. Stimulates adrenal cortex to secrete glucocorticoids2. Tropic hormones – cause release of other hormones v. PRL-prolactin1. After birth stimulates mammary glands to synthesize milk, enhances secretion of testosterone by testes2. Stimulates production of milk (but not its release)vi. GH-growth hormone1. Stimulates mitosis and cellular differentiationvii. Hypothalamic releasing and inhibiting hormones travel in hypophyseal portal system to anterior pituitary1. Portal system – system of capillary beds connectedviii. Hypothalamus takes in info, decisions made in hypothalamus, execution done in anterior pituitaryc. Hypothalamo-Pituitary-Target Organ Relationshipsi. *All hypothalamic and pituitary hormones are peptidesii. Negative feedback inhibition 1. Ex: T3 and T4 produced because of TSH, which happens because of TRHa. T3 and T4 will put brakes on further production II. Pineal Glanda. Neurological stimulusb. Takes in info about lightc. Not all light that comes in is used to form an imaged. Synchronizes physiological function w/ 24-hour circadian rhythms of daylight anddarknesse. Synthesizes melatonin from serotonin during the night f. Produces melatonin or serotonin depending on whether it is day or nighti. At night, activity decreases; go to sleep - melatoninii. When you wake up, more brain activity-serotonin elevates neuronal activityg. Disordersi. Season Affective Disorder (SAD) occurs in winter/northern climatesii. Symptoms: depression, sleepiness, irritability and carbohydrate craving III. Thyroid Glanda. Made of spherical balls (follicles) – simple cuboidal epithelium i. Inside: filled w/ colloid (precursors to hormone stored)ii. Follicles release T3 and T4 b. T3 and T4 is composed of 2 tyrosines and 2-4 iodine ionsi. Iodine absorptionii. Thyroglobulin synthesis (tyrosine-rich protein)iii. Iodine added to tyrosines of thyroglobuliniv. Thyroglobulin uptake and hydrolysisv. Release of T4 and small amount of T3 into blood 1. Hydrophobic hormone – intracellular c. Decrease temp (stimulus) => TRH/TSH => TH => increase metabolic rate (temperature, O2 effects), increase appetite, increase GH secretiond. Disordersi. Congenital hypothyroidism (decreased TH)1. Hyposecretion present at birth (formerly cretinism)2. Can be treated w/ oral thyroid hormoneii. Myxedema (decreased TH)1. Adult/adolescent hypothyroidism iii. Goiter1. Pathological enlargement of thyroid gland2. Dietary iodine deficiency, hyposecretion of TH3. Thyroid hormone levels low but thyroid stimulating hormone levels high – no negative feedback4. No ability to regulate body temp, more sluggishiv. Graves Disease (hyperthyroidism)1. Antibodies mimic effect of TSH on thyroid 2. High body temp and activity level3. Thinner body 4. Eyes protrudev. Hyperthyroidism1. Patient exhibiting hyperactivity and elevated body temp has bloodtest:a. T3 and T4 elevatedb. TRH levels lowc. TSH levels high2. If T3 and T4 high (thyroid), expect inhibition of TRH (consistent)3. If TRH are low, TSH should also be lowa. TRH – from hypothalamusb. TSH – from anterior pituitaryc. Given high levels of TSH, should have high levels of T3 and T4 (consistent)4. Problem: hypersecretion of TSH e. C cells = parafollicular cellsi. Make calcitoninii. Increase levels of calcium => we produce calcitonin (from thyroid gland) => increase osteoblast activity, decrease PTHIV. Parathyroid glandsa. Decrease calcium => PTH => increase osteoclast activity, increase calcium reabsorption from kidneys (lose it temporarily to urine, then pull it back-reclaiming calcium from urine production), increase calcitrol (comes from vitaminD [kidney]-so can absorb calcium from digestive tract)b. Keep calcium levels HIGHc. Disordersi. Hypoparathyroidism1. Accidental excision during surgery2. Decline in blood calcium3. Fatal tetany in 3-4 daysa. Diaphragm is overstimulated due to change in ionic environmentii. Hyperparathyroidism1. Parathyroid tumor2. Calcium and phosphate blood levels increase3. Spontaneous calcifications occur throughout bodyV. Pancreatic Isletsa. Alpha cells secrete glucagonb. Beta cells secrete insulinc. (Exocrine glands – gland w/ ducts)d. Hormones produced by cells of islets that go into blood (endocrine) e. 4 distinct cell typesi. Alpha, beta, delta, F cellsf. Stabilizing glucosei. Increase glucose levels (hyperglycemia) => insulin => hypoglycemic effects(lower glucose)1. Stimulates cells to absorb glucose2. Promotes synthesis of glycogen (in muscles and liver)3. Suppresses use of stored fuelsii. Note: brain, liver, kidneys, and RBCs absorb glucose w/out insuling. Diabetes Mellitusi. Mellitus: means that urine is sweet 1. “Honey” ii. Diabetes Insipidus iii. Both characterized by excessive urine production iv. Diabetes mellitus – affects mostly westernized countries v. High amounts of blood sugar1. Due to hyposecretion of insulin 2. Or inactivation of insulin signaling systemvi. Diagnosis: revealed by elevated blood glucose, glucose in urine, polyuria and dehydration, ketones in urine1. Glucose transporters can only work so fast2. W/ high blood sugar, lose glucose to urinevii. Types1. Type Ia. IDDM – insulin dependent diabetes