Repro- Gonadal Axis

Card Set Information

Repro- Gonadal Axis
2015-08-29 10:10:58
vetmed repro

vetmed repro
Show Answers:

  1. What is the difference b/w the male and female hypothalamus?
    surge center in female (defeminized in male)
  2. The portal system drains into the ________ only.
    adenohypophysis/ anterior pituitary/ pars distalis
  3. In females, there is a pre-ovulatory ________ surge; in males, there is _________.
    GnRH; tonic GnRH release
  4. How does the hypothalamus communicate with the posterior pituitary?
    direct release of neuropeptides into capillaries of neurohypophysis
  5. 5 Protein hormones.
    oxytocin, GnRH, FSH, Prl, LH
  6. Protein hormones bind to _______ to...
    membrane receptors; activate a signaling cascade.
  7. 3 steroid hormones.
    testosterone, estradiol, progesterone
  8. Steroid hormones cross the ________ to bind to ________ to...
    cell membrane; nuclear receptors; activate transcription.
  9. ________ produce steroid hormones from __________.
    Gonads; cholesterol
  10. The LH surge causes _________ production.
    progesterone (progesterone during pregnancy inhibits new follicles from developing and ovulating--> to sustain current pregnancy)
  11. Describe the pathway of LH in a male.
    hypothalamus--> GnRH--> anterior pituitary--> LH pulse--> leydig cells--> testosterone production--> sertoli cells--> spermatogenesis OR testosterone--> DHT--> circulation OR testosterone--> estradiol
  12. Describe the pathway of FSH in a male.
    hypothalamus--> GnRH--> anterior pituitary--> FSH--> sertoli cell--> ABP (androgen-binding protein)--> ABP binds testosterone in lumen of seminiferous tubules--> accumulutes in lumen--> critical for normal spermatogenesis
  13. Why does ABP accumulate in the lumen of the seminiferous tubules and bind testosterone?
    ABP is too large to pass through the luminal walls
  14. Describe negative feedback of GnRH in males.
    FSH--> sertoli cells--> inhibin and ABP--> inhibin goes to pituitary--> inhibits FSH secretion
  15. Describe the pathway of gonadotropins in a female.
    LH and FSH stimulate follicular growth--> increase in estradiol--> hypothalamus--> GnRH surge--> anterior pituitary--> LH surge--> ovulation
  16. Describe negative feedback of GnRH in females.
    FSH--> follicle produces inhibin--> inhibin goes to pituitary--> inhibits FSH secretion
  17. LH affects _______ cells in a female.
  18. FSH affects ________ cells in a female.
  19. Describe the general pathway for steroid hormones.
    steroid secreted by gonad--> enters blood and goes to target tissue--> causes change in target tissue--> steroid in blood passes through liver--> liver renders steroid water soluble--> steroid re-enters blood--> goes to kidney and bile--> excreted in urine and/or feces
  20. Steroid hormones are metabolized in the _________.
  21. After steroid hormones have been metabolized, they are excreted as __(2)__.
    glucuronide or sulfate