Intraperitoneal kisspeptin-10 administration induces dose-dependent degenerative changes in maturing rat testes.

Abstract Aims Kisspeptin, a peptide secreted by hypothalamic neurons, is a critical regulator of reproduction and puberty but its role in the regulation of gonadal maturation in sexually immature males is elusive. The present study investigated the effects of 12 days of pulsatile kisspeptin administration on gonadotropins and testosterone release and maturation of immature male gonads. Main methods Kisspeptin-10 was administered intraperitoneally at different dosage concentrations (1 μg, 1 ng, and 10 pg) to 5 weeks old prepubertal male rats, twice daily for 12 days. Plasma LH, FSH and testosterone concentrations were measured through competitive-binding radioimmunoassay. Spermatogenesis was studied mainly at stage VII of the spermatogenic cycle through light and electron microscopy. Key findings At the end of the treatments plasma LH and testosterone concentrations were reduced significantly at 1 ng and 1 μg kisspeptin doses ( P P P P P P Significance In conclusion long-term kisspeptin-10 administration negatively regulates gonadal maturation in prepubertal testes.