S2M3 physio

-pulsatile release of GnRH

• - breast buds before 8 or lack of development by 13
• - requires further investigation

• - Tanner stage 4
• - first menses
• - cycles during first 6-12 months are usually irregulat and anovulatory

• - theca interna- reponds to LH in very low levels and synthesizes androstenodione
• - granulosa cells- respond to FSH in very low levels and secretes estrogen, inhibin and activin
• - secrete estrogens to regulate the follicular/ proliferative phase

• - secreted by the granulosa cell
• - low levels- supress release of GnRH, FSH and LH
• - 1 E of follicular phase is estradiol 17 B

• - supress release of FSH
• - secreted by the granulosa cell

• - stimulates FSH release
• - secreted by the granulosa cell

• - stimulate the HT==> increased GnRH secretion
• - increases FSH and LH
• - increased FSH then upreg LH-r in GC (periovulatory/late proliferative phase)
• - resulting in a high sustaines estradiol level

- hallmark indicator of ovulatory cerical secretion

- oocyte quality

• - ages 20-30
• - days 12 and 13 of cycle

• - secreted by the oocyte
• - stimulate GC
• - important in dominant follicle selection
• - blocking of these will prevent emergence of a dominant follicle

• M- <9
• F- <6-8

- Testosterone and FSH acting directly on Sertoli cells are primary regulators of spermatogenesis

• - sperm production
• - sex drive, behavior
• - skeleton
• - f/b suppression to anterior pituitary

• - early- low levels of LH and FSH cause E production, which causes proliferation of functional layer of endometrium
• - mid- E levels rising, but still inhibitory to HT/P
• - late- peak FSH, LH. High E causes HT/P f/b switch. High E for 48 hrs

• - early- leutinization of ruptured follicle=> CL form=> progesterone production
• - mid- fully developed CL, high P production, rescue by hCG during "window of implantation"
• - late- if no hCG CL dies, P decreases and menses will follow

• - aka late proliferative phase
• - high FSH (vie high E) lead to upred of LH-r on GC==> progesterone formation
• - upreg of LH-r and progesterone are required for ovulation to occur
• - ~48 hrs after E spike=>LH surge=> ovulation (~10 hours after LH surge)

• - occurs during ovulatory window as a result of LH and P surge
• - increase in [Ca]cyt indicates meiosis has resumed
• - newly formed 2ndary oocyte (and PB1) arrest in metaphase II untill fertilization

• - removal of no longer required substances from surface of sperm once they enter the oviduct
• - final step is hyperactivation (faster and circular mvmt)
• - functional maturation of sperm preparing them for the acrosomal reaction

• - initiated when sperm contact ZP
• - involves binding and subsequent b/d of ZP to allow sperm entry and fusion with oocytes