Abstract
Gonadotropin releasing hormone (GnRH) is one of the key factors in the neuroendocrine regulation of reproduction in vertebrates. Some fish have three variants of GnRH: GnRH1 involved in the secretion of gonadotropins, GnRH2 that regulates feeding and sexual behaviors and GnRH3 expressed in the olfactory bulb and the nerve terminal nerve, wich innervate the retina and the olfactory epithel…