Growth response of adult germ cells to rat androgen-binding protein and human sex hormone-binding globulin.
Androgen-binding protein (ABP) is produced by Sertoli cells depending on the development and the stage of the spermatogenic cycle. Germ cell proliferation is at its peak when ABP is at its peak and secreted towards the testicular basal compartment containing spermatogonia and premeiotic spermatocytes. Rat isolated adult germ cell DNA synthesis was studied in vitro in the presence of ABP with and without steroids and in the presence of pure or recombinant sex steroid hormone-binding globulin (SHBG) using thymidine incorporation. Results are: SHBG is able to promote DNA synthesis in the absence of cofactors. Testosterone reacted negatively to the stimulatory effect of SHBG. We conclude that ABP, the physiological steroid-binding protein, should be considered as a paracrine regulator of spermatogenic DNA synthesis in the adult rat.
Gérard
A
A
Laboratoire d'Histologie-Embryologie II, Faculté de Médecine de Nancy, Vandoeuvre-lés-Nancy, France.
Bedjou
R
R
Clerc
A
A
Maachi
F
F
Closset
J
J
Hammond
G L
GL
Nabet
F
F
Gérard
H
H
D000727:Androgen-Binding Protein / Q000494:pharmacology*; D000818:Animals; D002417:Cattle / Q000097:blood / Q000196:embryology; D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D004247:DNA / Q000096:biosynthesis; D005312:Fetal Blood; D008297:Male; D051381:Rats; D012738:Sex Hormone-Binding Globulin / Q000494:pharmacology*; D013094:Spermatozoa / Q000166:cytology* / Q000378:metabolism; D013936:Thymidine / Q000378:metabolism
D000727:Androgen-Binding Protein; D012738:Sex Hormone-Binding Globulin; D004247:DNA; D013936:Thymidine