182 female endo I Flashcards
what is secreted after ovulation and has neg feedback?
Progesterin
GnRH
peptide -> 7 GPCR -> PLC -> IP3/DAG pathway -> gene transcription
gonadotroph
one cell makes LH and FSH
common a - subunit (TFLh)
what cause male hormone effects?
DHT via 5 a reductase
what does aromatase do?
converts testorone to estrogen in peripheral tissue
ovary steroid productiion
androgen –> estrogen –> circulation via SBG (sex binding globulin) and albumin
what causes local estrogen production?
aromatase converts androgen to estrogen
CNS, fat, breast tissue
sex steroid action
nuclear receptors and surface receptors (more rapid response
andogren - SBG concnetration is important - sponge like action + 5 a reductase presence
inhibins and activins
important in feedback from testis and ovaries - inhibins in endocrine fashion
inhibin –I FSH
paracrine and autocrine fashion too
TGF-B superfamily
female reproduction hormones
suppressed until puberty
GnRH is pulsatile (continous suppresses LH and FSH) –> LH is very pulsatile and FSH less so
starts during sleep but then is pulsing throughout the day
high freq GnRH pulses
favors LH release - no big affect on FSH
average freq
LH and FSH
low freq
favors FSH
progesterone
lows GnRH pulse freq –> decreases LH and increases FSH
estradiol
can increases or decreases GnRH freq
+ during midcycle LH surge
- the rest of the time
