Hormonal dependence of the first spermatogenic wave in the mouse

Antiserum to rat gonadotropins (arG) has been proved capable of binding homologous luteinizing hormone (LH) and follicle stimulating hormone (FSH) in vitro and mouse LH and FSH in vivo. The administration of arG did not evoke antibody production. The physiological role of endogenous gonadotrophins during neonatal life was studied by administration of this antiserum to groups of newborn male mice. Daily injection of arG from birth up to the age of 100 days inhibited markedly weight increase of testes and accessory glands. Histological evaluation of the testes of such treated animals revealed that spermatogenesis up to the stage of pachytene spermatocytes can proceed in the absence of endogenous gonadotropins; however, no spermatids were formed and the number of cells that developed in the hormone-deprived animals was significantly lower than in the normal animal. Substitution treatment with exogenous FSH permitted the formation of a small number of spermatids, but completion of spermatogenesis was obtained only with combined LH and FSH treatment.