Flashcards in Male Reproductive Physiology Deck (13):
what cells secrete Mullerian inhibiting factor? what is the function of MIF?
Sertoli cells; suppresses development of paramesonephric (Mullerian) ducts
what cells secrete androgens? what is the function of androgens?
Leydig cells; stimulate development of mesonephric (Wolffian) ducts --> male phenotype
what does the mesonephric duct develop into in the male fetus?
male internal structures (except prostate): Seminal vesicles, Epididymis, Ejaculatory duct, Ductus deferens
what is the function of 5alpha-reductase?
converts testosterone to DHT (dihydrotestosterone)
why do men have circulating estrogens?
expression of aromatase in peripheral (particularly adipose) tissue
what enzyme converts testosterone to DHT (dihydrotestosterone) and why is this necessary?
5alpha-reductase; DHT has a higher affinity for androgen receptor in nucleus of target cells
what two hormones are major stimulators of spermatogenesis?
FSH and local testosterone
functions of testosterone (5)
1. differentiation of epididymis, vas deferens, seminal vesicles (genitalia, except prostate)
2. growth spurt: penis, seminal vesicles, sperm, muscle, RBCs
3. deepening of voice
4. closing of epiphyseal plates (via estrogen converted from testosterone)
where is inhibin made and what is its function?
Sertoli cell; inhibits only FSH release from anterior pituitary
what hormone stimulates the Leydig cell and what is its main function?
LH; produces testosterone which has system androgenic effects and has local intra-testicular effects by diffusing into the Sertoli cell, increasing the response to FSH
what hormone stimulates the Sertoli cell and what is its main function?
FSH; stimulates spermatogenesis and makes inhibin
analogous cells in female and male gonads
leydig cell (testis) = theca interna cell (ovary)
Sertoli cell (testis) = granulosa cell (ovary)