SB223412, a neurokinin-3 receptor-selective antagonist, suppresses testosterone secretion in male guinea pigs.

Guinea pigs are important zoo animals and have been recommended for animal-assisted activities or therapy, however there are problems concerning testosterone inducing aggressive or sexual behaviors in male guinea pigs. Testicular testosterone secretion is regulated by pulsatile gonadotropin releasing hormone (GnRH)/luteinizing hormone (LH) release in mammals. The mechanism generating GnRH/LH pulses is thought to be governed by kisspeptin neurons, which coexpress neurokinin B (NKB) and dynorphin A (Dyn), in the arcuate nucleus (ARC).