BIOL 252 1st Edition Lecture 14 Outline of Last Lecture I Modes of ATP Synthesis During Exercise II Fatigue III Classes of Muscle Fibers IV Cardiac Muscle V Smooth Muscle VI Intercellular communication VII Principles of hormone communication VIII Classes of Hormones IX Hormone Receptors and effects X Endocrine disorders XI Hypothalamus and Pituitary Outline of Current Lecture I Pituitary II Pineal Gland III Thyroid Gland IV Parathyroid glands V Pancreatic Islets Current Lecture I Pituitary a Posterior Pituitary Hormones i ADH see previous lecture ii Oxytocin 1 Produced in hypothalamus 2 Transported by hypothalamo hypophyseal tract to posterior lobe 3 Neural stimulus OT smooth muscle contraction uterus reproductive ducts and mammary glands promotes emotional bonding a The love hormone 4 OT promotes release of milk b Anterior Pituitary Hormones i FSH follicle stimulating hormone These 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 II III 1 Stimulates secretion of ovarian sex hormones development of ovarian follicles and sperm production ii LH luteinizing hormone iii TSH thyroid stimulating hormone 1 Stimulates secretion of thyroid hormone 2 Tropic hormone iv ACTH adrenocorticotropic hormone 1 Stimulates adrenal cortex to secrete glucocorticoids 2 Tropic hormones cause release of other hormones v PRL prolactin 1 After birth stimulates mammary glands to synthesize milk enhances secretion of testosterone by testes 2 Stimulates production of milk but not its release vi GH growth hormone 1 Stimulates mitosis and cellular differentiation vii Hypothalamic releasing and inhibiting hormones travel in hypophyseal portal system to anterior pituitary 1 Portal system system of capillary beds connected viii Hypothalamus takes in info decisions made in hypothalamus execution done in anterior pituitary c Hypothalamo Pituitary Target Organ Relationships i All hypothalamic and pituitary hormones are peptides ii Negative feedback inhibition 1 Ex T3 and T4 produced because of TSH which happens because of TRH a T3 and T4 will put brakes on further production Pineal Gland a Neurological stimulus b Takes in info about light c Not all light that comes in is used to form an image d Synchronizes physiological function w 24 hour circadian rhythms of daylight and darkness e Synthesizes melatonin from serotonin during the night f Produces melatonin or serotonin depending on whether it is day or night i At night activity decreases go to sleep melatonin ii When you wake up more brain activity serotonin elevates neuronal activity g Disorders i Season Affective Disorder SAD occurs in winter northern climates ii Symptoms depression sleepiness irritability and carbohydrate craving Thyroid Gland a Made of spherical balls follicles simple cuboidal epithelium i Inside filled w colloid precursors to hormone stored b c d e ii Follicles release T3 and T4 T3 and T4 is composed of 2 tyrosines and 2 4 iodine ions i Iodine absorption ii Thyroglobulin synthesis tyrosine rich protein iii Iodine added to tyrosines of thyroglobulin iv Thyroglobulin uptake and hydrolysis v Release of T4 and small amount of T3 into blood 1 Hydrophobic hormone intracellular Decrease temp stimulus TRH TSH TH increase metabolic rate temperature O2 effects increase appetite increase GH secretion Disorders i Congenital hypothyroidism decreased TH 1 Hyposecretion present at birth formerly cretinism 2 Can be treated w oral thyroid hormone ii Myxedema decreased TH 1 Adult adolescent hypothyroidism iii Goiter 1 Pathological enlargement of thyroid gland 2 Dietary iodine deficiency hyposecretion of TH 3 Thyroid hormone levels low but thyroid stimulating hormone levels high no negative feedback 4 No ability to regulate body temp more sluggish iv Graves Disease hyperthyroidism 1 Antibodies mimic effect of TSH on thyroid 2 High body temp and activity level 3 Thinner body 4 Eyes protrude v Hyperthyroidism 1 Patient exhibiting hyperactivity and elevated body temp has blood test a T3 and T4 elevated b TRH levels low c TSH levels high 2 If T3 and T4 high thyroid expect inhibition of TRH consistent 3 If TRH are low TSH should also be low a TRH from hypothalamus b TSH from anterior pituitary c Given high levels of TSH should have high levels of T3 and T4 consistent 4 Problem hypersecretion of TSH C cells parafollicular cells i Make calcitonin IV V ii Increase levels of calcium we produce calcitonin from thyroid gland increase osteoblast activity decrease PTH Parathyroid glands a Decrease calcium PTH increase osteoclast activity increase calcium reabsorption from kidneys lose it temporarily to urine then pull it backreclaiming calcium from urine production increase calcitrol comes from vitamin D kidney so can absorb calcium from digestive tract b Keep calcium levels HIGH c Disorders i Hypoparathyroidism 1 Accidental excision during surgery 2 Decline in blood calcium 3 Fatal tetany in 3 4 days a Diaphragm is overstimulated due to change in ionic environment ii Hyperparathyroidism 1 Parathyroid tumor 2 Calcium and phosphate blood levels increase 3 Spontaneous calcifications occur throughout body Pancreatic Islets a Alpha cells secrete glucagon b Beta cells secrete insulin c Exocrine glands gland w ducts d Hormones produced by cells of islets that go into blood endocrine e 4 distinct cell types i Alpha beta delta F cells f Stabilizing glucose i Increase glucose levels hyperglycemia insulin hypoglycemic effects lower glucose 1 Stimulates cells to absorb glucose 2 Promotes synthesis of glycogen in muscles and liver 3 Suppresses use of stored fuels ii Note brain liver kidneys and RBCs absorb glucose w out insulin g Diabetes Mellitus i 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 sugar 1 Due to hyposecretion of insulin 2 Or inactivation of insulin signaling system vi Diagnosis revealed by elevated blood glucose glucose in urine polyuria and dehydration ketones in urine 1 Glucose transporters can only work so fast 2 W high blood sugar lose glucose to urine vii Types 1 Type I a IDDM insulin dependent diabetes mellitus b Insulin is always used to treat c Hereditary susceptibility d Autoantibodies attach and destroy pancreatic beta cells 2 Type II a NIDDM non insulin dependent b Insulin resistance c Risk factors are heredity