Kisspeptin: A Central Regulator of Reproduction in Mammals

Abstract

The discovery of the role of kisspeptin neurons in the regulation of mammalian reproduction in 2003 was one of the biggest breakthroughs in reproductive endocrinology within the last few decades. Research during the past two decades since the discovery of kisspeptin has been unveiling the mechanism of how the hypothalamic kisspeptin neurons control reproductive functions through regulation of gonadotropin-releasing hormone (GnRH) secretion. This article aims to overview kisspeptin research, including the most recent studies from ours and other research groups, and to discuss the possibility of new strategies to control reproductive functions in farm animals. In the first section, we introduce the critical role of kisspeptin neurons in puberty onset and reproductive functions in mammals, including the regulation of two modes of GnRH/gonadotropin secretion, namely pulsatile and surge modes. The next section focuses more on the mechanism of how the kisspeptin neurons in the arcuate nucleus in the hypothalamus precisely controls GnRH pulse using other two neuropeptides, neurokinin B and dynorphin A. The article also discusses the mechanism suppressing reproductive function during lactation and other stress conditions through inhibition of kisspeptin neurons and consequent GnRH/gonadotropin secretion, to provide insights on the possibility of new strategies to control reproductive performance in domestic farm animals. Keywords Anteroventral Periventricular Nucleus, Arcuate Nucleus, Fertility, Gonadotropins, Pre-optic Area.