Female physiology Smith 11/1/16 TEST #3 Flashcards
What is the key hormone released from the HPO loop from the hypothalamus?
-Gonadotropin-Releasing Hormone (GnRH)
What is the key trophic hormone released from the anterior pituitary during the HPO loop?
- Follicle-Stimulating Hormone (FSH)
- Luteinizing Hormone (LH)
What are the key target hormones released from the ovary in the HPO loop?
- Estrogens
- Progesterone
- Inhibins
What type of cells provide androgens which stimulate the granulosa cells and produce the circulating estrogens?
-Thecal cells
The estrogens released from the thecal cells feedback inhibit what hormones?
- GnRH
- LH
- FSH
What do inhibins do?
-Inhibit FSH secretion
Where are inhibins released from?
-granulosa cells
What stimulates the thecal cells?
LH
What stimulates the granulosa cells?
- LH
- FSH
What are the three types of estrogens?
- Estradiol (E2)
- Estrone (E1)
- Estriol (E3)
What estrogen hormone is the predominant estrogen during reproductive years?
-Estradiol (E2)
What estrogen hormone is predominant in menopause?
-Estrone (E1)
What estrogen hormone is predominant in pregnancy?
-Estriol (E3)
What are physiological functions of estrogen?
- Sexual maturation
- Increase CNS excitability
- Stimulate uterine growth
- Reduce rate of bone -readsorption
- Increase HDL
- Decrease LDL
When is the most fertile time during the menstrual cycle?
9-15 days
At what point is Estrogen at a low point?
Menses
What hormones does low estrogen during menses cause the pituitary to secrete?
- FSH
- LH
What do FSH and LH do?
-Stimulate growth of several preovulatory ovarian follices
Prior to ovulation what acts predominantly on the theca cells?
LH
Estradiol (E2) increases, inhibits what hormone release?
- FSH
- LH
What does the inhibited release of FSH and LH do to follicles?
-Starve some of the follicles allowing one dominant secondary follicle to survive
What causes the FSH and LH to accumulate in the anterior pituitary?
-Prolonged high levels of estrogen
What causes the LH surge?
E2 (Estradiol) reach a tipping point
What does the tipping point of E2 levels do to the hypothalamus?
-Stimulate the release of more GnRH that tell the Anterior pituitary to release stored LH
What does the LH surge cause?
-Ovulation
What are remaining ovarian cells called?
-Corpus luteum
What does the corpus luteum produce?
-High amounts of progesterone
T/F
The elevated progestrone and estrogen level of the luteal phase will inhibit the pituitary release of LH and FSH that usually helps a second ovulation event occur
False
it prevents a second ovulation event