Oh, the Secretions I’ll Learn!

1. Oh, the Secretions I’ll Learn! The Endocrine Glands and Their Hormones Anatomy Chapter 11

2. The Pituitary Gland

3. found at base of brain (sellaturcica) • 2 endocrine glands in one! • attached to hypothalamus by stalk • once considered master gland, but is known to be controlled by hypothalamus

5. Posterior Pituitary Gland aka neurohypophoysis (neuro=nerve) composed of nerve cells/fibers & neuroglia 2 hormones: 1. antidiuretic hormone-ADH- accelerates re-absorption of water from urine in kidneys decreases volume of urine released 2. oxytocin- secreted by females before and after birth of child

6. Anterior Pituitary Gland • aka adenohypophysis (adeno=gland) • 6-7 hormones • many of these hormones will stimulate another endocrine gland to grow & secrete its hormones (tropic hormones) • will affect: thyroid, adrenal cortex, ovarian follicles, corpus luteum

7. Tropic Hormones 1. thyroid stimulating hormone -TSH- acts on thyroid causes it to secrete thyroid hormone 2. adrencorticotropic hormone –ACTh- acts on adrenal cortex causes it to grow & secrete its hormones

8. 3. follicle-stimulating hormone-FSH- stimulates follicles to start to grow causes them to secrete estrogen (females) (in males) stimulates cells to grow and form sperm

9. 4. luteinizing hormone-LH- aka ovulating hormone stimulates follicles & ovum to grow & mature releases estrogen causes ovulation (females) produces progesterone (males) testes develop; secrete testosterone

10. Non-tropic Hormones 5. growth hormone –GH- stimulates cells to increase in size & divide frequently promotes normal growth has to be balanced with blood glucose level

11. Gigantism

12. Classic Acromegaly

13. Acromegaly

14. Dwarfism

15. 6. melanocyte-stimulating hormone-MSH causes synthesis & dispersion of melanin by melanocytes may regulate ACTh 7. prolactin- stimulates milk production after birth found in males, but purpose not known

16. Thyroid Gland

17. Thyroid Gland • vascular • below larynx & on sides & front of trachea • hypothalamus & pituitary gland controls • 2 hormones released

18. thyroxine aka tetraiodothyronine, T4(contains 4 iodine atoms) 2. triiodothyronine, T3 (contains 3 iodine atoms) most potent & principle hormone (5x stronger)

19. purposes: • regulate metabolism of carbs, lipids, proteins by: • increasing rate which cells release energy from carbs • incr rate of protein synthesis • stimulate breakdown & mobilization of lipids

20. basal metabolic rate (BMR) the amount of calories the body must consume to maintain life at rest required for normal growth/development required for nervous sys to mature MUST have iodine *unique thyroid only gland to store hormones insufficient iodine = goiter

23. calcitonin- not actually considered true hormone • regulates conc of bld calcium & phosphate ions • the conc of calcium is what regulates release of calcitonin

24. Parathyroid Glands • found on posterior of thyroid gland • 4 glands • composed of secretory cells covered in connective tissue

25. secrete parathyroid hormone –PTH- increases blood calcium concentration and decreases blood phosphate conc affects bones, kidneys, intestines increases a below normal bld calcium conc

26. Adrenal Glands • found atop kidney (cap) • vascular • consists of 2 glands in one • each releases different hormones

28. adrenal medulla • composed of nerve cells • cells connected with sympathetic nervous system • hormones NOT VITAL for life • secretes 2 hormones: • epinephrine (adrenalin) • norepinephrine (noradrenalin)

29. epinephrine makes up 80% of secretions • both hormones have same effects as nerves on cell but lasts 10x longer • hypothalamus responds to stress, sends impulses to a.m. • body prepares for “fight or flight”

30. adrenal cortex • makes up bulk of adrenal gland • composed of epithelial cells • vascular • produces > 30 steroids • many VITAL to life • 3 main hormones:

31. 1. aldosterone • type of mineralocorticoid • helps regulate conc of mineral electrolytes • affects kidneys to conserve Na+ and excrete K+ • stimulates water retention • conc levels of Na+, K+, or kidney will affect hormone’s release

32. 2. cortisol • aka-hydrocortisone • type of glucocorticoid- affects glucose metabolism, and metabolism of fats and proteins • actions of hormone help blood glucose levels to stay within normal range between meals

33. 3. adrenal sex hormones • most male hormones (androgens), but changed to female hormones • stimulates early development of reproduction organs

34. Cushing’s disease

35. Pancreas • 2 glands in one! • 2 major secretory cells • exocrine portion secretes digestive enzymes • endocrine releases hormones • endo cells are grouped in clusters called: islets

36. islets contain 2 types cells: • alpha – secrete hormone glucagon • beta- secrete hormone insulin

37. glucagon – stimulates liver to breakdown glycogen into glucose raises blood sugar level prevents hypoglycemia when glucose conc is low or used rapidly

38. insulin- stimulates liver to form glycogen from glucose & inhibits conversion of noncarbs into glucose *only hormone to decrease blood sugar levels normal bld sugar level 80-120mg

39. too little insulin-type I diabetes • abnormality of insulin type II diabetes

40. Pineal Gland • aka - third eye • near thalamus • secretes melatonin which regulates circadian rhythms- patterns of repeated activity associated with cycles of day and night

42. helps body tell difference between day and night • may control onset of puberty • resembles pine cone

43. Thymus Gland