Female Reproductive Hormones Physiology

  1. Most of estrogen and progestin are made from _____
  2. What are different forms of estrogen and where are they made from?
    • Beta estradiol (from ovaries)
    • Estrone (peripheral tissues)
    • Estriol (liver)
  3. Which hormone influence cholesterol conversion to pregnenolone?
    LH in theca cells
  4. Which hormone play a role in stimulating aromatase to convert testosterone to estradiol?
    FSH in granulosa cells
  5. What is the enzyme that converts pregnenolone to progesterone?
    3beta-hydrodxysteroid dehydrogenase
  6. The first enzyme in cholesterol conversion to estradiol is ______. This process occurs in _____ cells
    • Cholesterol desmolase
    • Theca
  7. 17 alpha hydroxylase is involved in converting ______ to ______. 17,20 lyase converts ______ to _____.
    • Pregnenolone to 17-hydroxypregenolone
    • 17 hydroxypregenonlone to DHEA
  8. Conversion of androstenedione to testosterone occurs in _____ cells, and involves ______ enzyme
    • Granulosa
    • 17 beta hydroxysteroid dehydrogenase
  9. T/F: Adrenal gland produces estradiol
    True; but only a limited amount, majority is produced in the ovaries
  10. T/F: progesterone can be converted to aldosterone
    True; couple steps involved, but immediately from progesterone via 21 hydroxylase you make deoxycorticosterone and then the 18 hydroxylase and oxidase will take you there
  11. Majority of estrogen and progesterone is bound to _____ in circulation
    • Albumin (60%)- estradiol
    • Protein- progesterone (although albumin is a protein, so albumin is most probably true too)
  12. Liver conjugates estrogens to _____ and ______.
    Glucuronides and sulfates
  13. T/F: liver also converts estradiol and estrone to the weaker estriol
  14. T/F: Liver can convert progesterone to other steroids within minutes of secretion
    False; it degrades progesterone to other steroids, major end product is pregnanediol
  15. Major end product of liver progesterone degradation is ______ , and this can be found in urine, which is used to estimate rate of progesterone ______
    • Pregnanediol
    • Formation
  16. LH receptors are found in _______ cell(s), FSH receptors are found in _______ Cell(s)
    • LH found in both theca and granulosa
    • FSH found only in granulosa
  17. Which cell has both LH and FSH receptors?
    Granulosa has both
  18. What is the 2 cell model?
    • Need both theca and granulosa cells to produce estrogen
    • Progesterone in granulosa cell goes into theca, which gets converted to androgen in there, and androgen is sent back to granulosa cell which ultimately gets converted to estrogen via aromatase
  19. T/F: the 2 cell model for estrogen production exists because only granulosa cell has FSH receptor, and that is needed for aromatase to convert androgen to estrogen
  20. Why can’t granulosa cell alone make estrogen, why does it involve theca cell?
    Granulosa cell cannot turn progesterone to androstenedione (precursor to androgen) because it lacks 17 alpha hydroxylase and 17,20 lyase in the cell, so must involve theca cells which contain those enzymes
  21. In mid menstrual cycle/ late follicular phase, estradiol exert a(n) _______ feedback to hypothalamus and anterior pituitary, which prompts _______ release of GnRH/FSH,LH respectively. This is known as ______
    • Positive
    • Increased
    • LH surge
  22. Between FSH and LH, which is stored more in the anterior pituitary?
    LH is stored more, whereas FSH is produced for a “just in time” purpose so not usually stored
  23. Factors that inhibit GnRH transcriptional signaling in gonadotrope?
    • Luteal phase: estrogen and progesterone
    • Inhibin from the ovary
  24. Factors that activate GnRH transcriptional signaling in gonadotrope?
    • Follicular phase: estrogen
    • Activin from ovary
  25. GnRH secretion frequency is increased by ______ and _____ neurons; GnRH secretion is decreased by _____ neuron
    • Kisspeptin and glutamate neurons
    • GABA inhibits it by inhbiting kisspeptin neurons
  26. At puberty, there is ____ activity of kisspeptin neurons and ____ in GABA.
    • Increased
    • Decreased (the decreased GABA also disinhibit kisspeptin)
  27. In puberty, GnRH receptor and LH receptor sensitivity _____ and there is also _____ surge in LH
    • Increase
    • Nocturnal surge
  28. Changes of hypothalamic neurons could be triggered by :
    • Increase in adipose tissue
    • Bone maturation
    • Leptin stimulation of GnRH
  29. T/F: Gonadotrophs are present before GnRH is in fetus.
    True; gonadotrophs present in week 10 of gestation and GnRH 14-16 weeks of gestation
  30. At week ______ gestation, the hypothalamic-pituitary system is functional and GnRH is released
  31. Continuous GnRH leads to _____ of gonadotropin release, vs pulsatile GnRH it would ______ gonadotropin release
    • Downregulate with continuous
    • Upregulate with pulsatile
  32. Why is there downregulation of gonadotropes with continued release of GnRH?
    GnRH receptor, when bound, leaves the membrane and enter the cell, so if GnRH is high constantly, the receptor cannot be replenished fast enough and the response of the gonadotrope decreases
  33. What could be the therapy for diseases that leads to high levels of estrogen?
    Continuous administration of GnRH analogs, because this would downregulate gonadotrope release
  34. There is a large increase in gonadotropin at ______, as shown in the spike in graph of total urinary gonadotropin
    Menopause, due to ovaries burnout
  35. At both low an high levels, ____ have inhibitory effect on hypothalamus and anterior pituitary. Whereas, at only high level of _____ would this have an inhibitory effect on the HPA.
    • Estrogen -both high and low
    • Progesterone – only high (low level of progesterone has stimulatory effect)
  36. When does estrogen exert a positive feedback to HPA?
    When the level increases past a threshold and stays above it from two days, estrogen starts to have a positive effect on the HPA. This is usually seen during late follicular phase – LH surge
  37. How is inhibin stimulated?
    FSH and estradiol stimulates granulosa cell to produce, and LH receptor on granulosa cell before ovulation can also stimulate
  38. Inhibit is produced by _____
    FSH and estradiol stimulating the granulosa cells
  39. T/F: inhibins decrease FSH and LH secretion by the gonadotrophs in the anterior pituitary
    False; they only decrease FSH as they have no effect on LH secretion
  40. T/F: Activins are released from the granulosa cells, therefore they increase FSH secretion from the anterior pituitary
    True; much like inhibin, activin only affect FSH, no LH activity
  41. Progesterone receptors are special, what are the two things that it can do?
    • Stimulate glandular secretion and membrane hyperpolarization
    • Signaling cascade can also inhibit intracellular calcium
  42. T/F: progesterone is mildly thermogenic (increases body temp in luteal phase)
  43. Which hormone is responsible for female reproductive tract maturation?
    • Estrogen
    • Increase sizes and development of glandular tissues
  44. What is the change in cell type of the vagina during puberty?
    cuboidal to stratified
  45. What is the effect of estrogen on skeleton?
    • Inhibits osteoclasts so they stimulate bone growth
    • Closes growth plates to end linear growth in puberty
  46. T/F: estrogen increases fat deposition in subcutaneous tissues, like the butt and thighs
  47. T/F: estrogen can act like aldosterone and cause sodium and water retention
    True; though usually insignificant but can be factor during pregnancy with estrogen levels super high
  48. T/F: estrogen stimulates breast development for milk production and make the breasts swell
    False; progesterone does that; estrogens effect on breast is that it stimulates outward appearance and increases stromal tissue and duct and fat on it
  49. Default human is _____ (sex)
    Female – without SRY gene. SRY gene leads to testes development
  50. Mullerian is to ____, and wolffian is to ____ (Sex)
    • Female/ uterus/ fallopian tubes
    • Male / epididymis/ vas deferens/ seminal vesicles
  51. Starvation would ____ leptin, which ____ Kisspeptin, and would therefore _____ GnRH
    • Decrease
    • Decrease
    • Inhibit
  52. Increase in TRH would ____ prolactin, which ____ kisspeptin and therefore_____ GnRH
    • Increase (remember everything increases prolactin, except dopamine)
    • Decreases
    • Inhibit
  53. Increased cortisol would have what effect to FSH/LH and GnRH?
    Inhibit both
Card Set
Female Reproductive Hormones Physiology
Endo Exam 2