Flashcards in Lecture 5 - Male Reproductive Tract I Deck (13):
Exocrine and endocrine secretions of testes?
spermatozoa and testosterone res[ectively
Primitive germ cells that become spermatozoa?
Stem cell factor?
drives migration and survival of PGCs; failure leads to germ cell migration (e.g. pancreas) and could lead to germ cell tumours
sertoli cells, and large round immature germ cells at the periphery
Germ cell tumours?
vast majority in testis, typically nervous tissue
produce testosterone, not testosterone dependent for first 7-8 weeks, 14 weeks gestation production of test becomes LH/hCG dependent; adult cells differentite from stem cells at puberty
Leydig cell location in fetl tissue?
interstium surrounding seminiferous cords
spike in testosterone secretion from Leydig cells 22 months post partum - masculinisation of neonatal brain, promoting sertoli cell proliferation, differentiation of gonocytes into spermatogonia
Sertoli cell function?
nurses cells that promote post-mitotic development: nourish spermatogonia, reabsorbing excess cytoplasm, produce seminiferous tubule fluid, maintain stem cell niche
Sertoli cell numbers?
proportional to sperm production capacity of seminiferous tubule - does not increase after puberty
Sertoli cell extra function?
blood-testis barrier (prevent antisperm antibody production) and immune privileged for transplants (e.g. islet cells)
suspened by caudal and gubernaculum ligaments in lumbar region, caudal regresses via testosterone, insulin-like 3 (from Leydig cells) dilates inguinal canal and causes gubernaculum to move toward,