The Effect of Kisspeptin on Male Rat Reproductive System

Abstract

Background: Kisspeptin (KP), a peptide secreted by the 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. Objectives: to investigate the effects of single dose of administration of KP on gonadotropins and testosterone release and maturation of immature rat male gonads.Materials & methods: Kisspeptin-10 was administered intraperitoneally at different dosage concentrations (50 and 12.5 nmol) to 45 days old prepubertal male rats, as single dose. Plasma LH, FSH and testosterone concentrations were measured. Spermatogenesis was histologically studied.Results: At the end of the treatments plasma LH increased significantly after 15 minutes, 6 hours and 24 hours. Testosterone concentration increased significantly after 15 minutes but decreased after 6 and 24 hours.Histologically, there was an evident degeneration of seminiferous tubules showing tubular necrosis, multinucleated giant cell formation, intratubular vacuolization, widened lumen and deshaped germ cells. Marked microscopic changes characterized by enlarged intratubular spaces, degenerative tissues filling tubular lumen and disrupted germ cells were noticeable.Conclusion: Pharmacological doses of kisspeptin-10 can cause induction of LH, FSH and testosterone and cause development of the spermatogonia but at high doses it causes testicular degeneration (dose dependent) in the prepubertal male rat