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(10 cards)
What forms the blood-testis barrier?
The tight junctions between Sertoli cells form the blood–testis barrier
What is located between sertoli cells other than tight junctions?
dividing germ cells
What is spermiation and what does it require in order for it to take place?
It is: the detachment of mature spermatozoa from the Sertoli cell into the lumen.
Requires: conversion of plasminogen to plasmin.
What do sertoli cells synthesize that is related to iron?
large amounts of transferrin for sperm development
What two hormones do sertoli cells bind?
Testosterone and FSH
What is the mechanism of signaling that FSH uses with sertoli cells?
FSH receptors are linked to adenylyl cyclase via G protein which activate cAMP and PKA
What does FSH stimulate the synthesis of in sertoli cells?
androgen-binding protein [ABP], plasminogen activator, inhibin, follistatin, and activin
What conversion does FSH indirectly induce?
It induces aromatase that converts androgens to estrogens
Q: What receptors do Leydig cells have, what do they stimulate, and how do they stimulate it?
A: Leydig cells have LH receptors that stimulate steroidogenesis through the nuclear transcription factor SF-1, which activates genes encoding CYP enzymes.
What stimulates steroidogenesis in the fetus instead of LH?
human chorionic gonadotropin (HCG)
