Kisspoptin signaling plays an essential role in the onset of puberty and reproductive development.Recently studies implicate that steroid-responsive NKB,kisspeptin,NK3 R,and estrogen receptor α (ERα) coexpress in arcuate nucleus of hypothalamus of variety of mammalian species and regulate the secretion of gonadotrophic hormone.The function of neurons in the hypothalamus is to regulate the estrogen negative feedback on gonadotropin-releasing hormone (GnRH) secretion.Loss of function of neurokinin B (NKB) or its receptor,the neurokinin-3 receptor produces idiopathic hypogonadotropic hypogonadism.These studies demonstrate NKB and neurokinin-3 receptor as the essential elements of the human reproductive axis.