Reproductive endo Flashcards
What are the steps of sexual differentiation?
- establishment of genetic sex
- translation of genetic sex
- translation of gonadal sex into phenotypic sex
what is the default pathway of sex differentiation that does not require hormones?
female pathway
what are prerequisites for successful sex differentiation?
- functioning sex determination genes
- fully functioning steroidogenic pathway and receptors
- normal chromosome complement
what are the duct differences btw males and females and what are they giving rise to?
males = Wolffian duct => vas deferens, epididymis females = Mullerian duct => uterus, oviduct
what is the urogenital sinus?
common before sex differentiation genitalia
what is the SRY gene?
part of MSY gene that doesn’t recombine
HMG region that binds to DNA to induce transcription of other genes
How can a male be XX and a female XY?
SRY transferred to X = sperm containing X and SRY = XX male
Abnormal SRY = does not transfer to phenotype = XY female
What are the transcription factors involved in sex determination?
+ SRY = SOX9 transcription = AMH (anti-mullerian duct) = male
- SRY = WNT4 + FOXL2 = female
What are the differences in hypothalamus differentiation btw males and females?
- males = testosterone produced by fetal testes not bound to a-FP => crosses BBB and converted to estradiol => estradiol in brain inhibit the dev of surge center
- females = estrogen binds to a-FP => no estradiol in brain leads to dev of surge center
what is tonic center?
part of the brain that regulates the release of LH and FSH post-puberty by releasing GnRH
what produces a-FP?
fetus liver
what are the functions of gonads?
gametogenesis and hormonogenesis = adiposity + muscle mass, fuel + pro metabol, electrolytes imbalances
What are the changes that occur during puberty related to the surge center?
surge center is really sensible to -ve feedback of steroids during the pre-pubertal phase
=> at puberty decrease in tonic center sensitivity = increases LH = dev + maturation of surge center in females + growing of gonads
where GnRH can be synthesized?
placenta, gonads, breast, lymphocytes, pituitary
what are the types of receptors that link LH and FSH?
G proteins that activate adenylate cyclase and PLC
what are the actions of LH and FSH?
- mobilization of chol in cells
- conversion to pregnenolone
- chol transport in mitochondria by StAR
- testes = LH steroidogenic (leydig cells)
- ovaries = LH + FSH are steroidogenic (granulosa and theca cells)
Explain the follicular waves.
GO
Explain hormone fluctuations according to the estrous cycle.
GO
