Endocrine system part 3

  1. Posterior Pituitary gland
    it does not synthesize hormones but it does store and release two hormones.  It consists of axons and axon terminals of more than 10,000 hypothalamic neurosecretory cells
  2. hypothalamohypophyseal tract
    this tract begins in the hypothalamus and ends near blood capillaries in the the posterior pituiatry
  3. Pituicytes
    the axon terminals in the posterior pituitary are associated with specialized neuroglia called this.  these cells have a supporting role
  4. oxytocin
    it affects the mothers uterus and breasts.  It is released from the posterior pituitary gland
  5. antidiuretic hormone (ADH)
    it decreases urin production.  It causes the kidneys to return more water to the blood.  Alcohol inhibits this hormone.  It also decreases the water lost through sweat and causes the constriction of arterioles which increases blood pressure. stored in the posterior pituitary gland
  6. Thyroid gland
    it is located just inferior to the larynx.  It is composed of left and right lateral lobes, one on either side of the trachea that are connected by the isthmus.
  7. thyroid follicles
    microscopic spherical sacs make up most of the thyroid glands.
  8. follicular cells
    the wall of each follicle consists primarily of these cells.  most of which extend to the lumen(internal space) of the follicle.  They secrete thyroid hormones
  9. Thyroxine or T4 and Triiodothyronine T3
    produced by thyroid gland also known as the thyroid hormones
  10. Parafollicular cells or C cells
    lie between follicles of the thyroid and produce calcitonin, which helps regulate calcium homeostasis.
  11. action of calcitonin
    can decrease the level of calcium in the blood by inhibiting the action of osteoclasts.
  12. Parathyroid glands
    are partially embedded in the posterior surface of the lateral lobes of the thyroid gland. They are small masses of tissue.
  13. chief cells
    produce parathyroid hormones
  14. Parathyroid hormone
    is the major regulator of levels of ca+2 , magnesium and phosphate ions.  It increases the number and activities of osteoclasts.  The result is elevated bone resorption.  It also acts on the kidneys to control the rate that Ca+2 and Mg+2 are lost in the urine.
  15. calcitrol
    a hormone that is the active form of vitamin D. PTH tells the kidneys to form this.
  16. Adrenal glands
    one of each lies superior to each kidney.  2 parts the cortex and the medulla
  17. adrenal cortex
    3 zones secret 3 different hormones.
  18. mineralocorticoids
    part of the adrenal cortex, it controls mineral homeostasis.
  19. Aldosterone
    produced by the mineralocorticoids in the adrenal cortex.  It regulates homeostasis of two ions, sodium and potassium and helps adjust blood pressure and blood volume.  It also supports the secretion of H+ in the blood to keep down acid in the blood
  20. RAA pathway
    controls secretion of Aldosterone
  21. Renin
    lower blood pressure stimulates cells in the kidneys to secrete this enzyme
  22. Angiotensinogen
    renin converts this plasma protein produced by the liver into angiotensin 2
  23. angiotensin 2
    converted from angiotensin 1.  this is what stimulated the adrenal cortex to secrete aldosterone
  24. Glucocorticoids
    part of the adrenal cortex. it regulates metabolism and resistance to stress. Cortisol is the most abundant hormone secreted the other two are corticosterone and cortisone
  25. corticotropin-releasing hormone (CRH)
    low blood levels of glucocorticouds, mainly cortisol, stimulate neurosecretory cells in the hypothalamus to secrete this. Which promotes the release of ACTH from the anterior pituitary which then flows to the adrenal cortex.
  26. Androgens
    produced by the adrenal cortex. In females they control libido and are converted into estrogens by other body tissues.  They stimulate the growth of pubic hair and contribute to growth spurts
  27. Adrenal medulla
    the inner region of the adrenal gland.  It is a modified sympathetic ganglion of the ANS
  28. chromaffin cells
    the hormone producing cells are innervated by sympathetic preganglionic neurons of the ANS.
  29. epinephrine and norepinephrine
    two major hormones of the adrenal medulla.  They intensify sympathetic responses in other parts of the body.
Card Set
Endocrine system part 3
Endocrine system part 3