Mechanisms of reproductive deficiency in male rats treated neonatally with a gonadotrophin-releasing hormone antagonist.
It is well known that males injected neonatally with oestradiol or antiserum or antagonists (ANT) against gonadotrophin-releasing hormone (GnRH) show multiple reproductive disorders. In the present work, in males treated neonatally with GnRH-ANT, we have analysed: (1) whether the impairment of reproductive function can be blocked by simultaneous treatment with gonadotrophins, (2) the possible differences in the effects of GnRH-ANT injected before or after the proliferation of Sertoli cells which takes place between days 1 and 15 of age, and (3) the mechanism(s) for the increased FSH secretion observed in adulthood. Experimental designs included: administration of GnRH-ANT between days 1 and 16 or 15 and 30 of age, simultaneous administration of gonadotrophins and GnRH-ANT to neonatal males, and measurement of FSH secretion after orchidectomy or specific destruction of Leydig cells with ethylene dimethane sulphonate (EDS) in adult males treated neonatally with GnRH-ANT. The principal new data presented in our studies are the following: (1) delayed puberty was observed not only in males injected neonatally with GnRH-ANT, but also in those injected with gonadotrophins or with GnRH-ANT and gonadotrophins, (2) the decreased fertility and increased FSH secretion observed in adult males treated neonatally with GnRH-ANT were normalized by simultaneous administration of GnRH-ANT and gonadotrophins, and (3) the increased FSH secretion in adult males treated neonatally with GnRH-ANT remained after EDS or orchidectomy, suggesting that mechanisms other than decreased inhibin secretion were involved in the increased secretion of FSH.
Pinilla
L
L
Department of Physiology, Faculty of Medicine, University of Córdoba, Spain.
Garnelo
P
P
Tena-Sempere
M
M
Gaytan
F
F
Aguilar
E
E
D000818:Animals; D000831:Animals, Newborn; D005298:Fertility / Q000187:drug effects*; D005640:Follicle Stimulating Hormone / Q000378:metabolism* / Q000494:pharmacology; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives* / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D007985:Leydig Cells / Q000187:drug effects; D007986:Luteinizing Hormone / Q000494:pharmacology; D008297:Male; D008698:Mesylates / Q000494:pharmacology; D009919:Orchiectomy; D051381:Rats; D017208:Rats, Wistar; D012741:Sexual Maturation / Q000187:drug effects*
D008698:Mesylates; D007987:Gonadotropin-Releasing Hormone; C042691:LHRH, N-acetyl-(4-chlorophenylalanyl)(1)-(4-chlorophenylalanyl)(2)-tryptophyl(3)-arginyl(6)-alanine(10)-; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; C002994:ethylene dimethanesulfonate