Gonadotropin-releasing hormone (GnRH),is a tropic peptide hormone responsible for the release of FSH and LH from the anterior pituitary. GnRH is synthesized and released from neurons within the hypothalamus.The vertebrate gonadotropin-releasing hormone (GnRH) is a decapeptide involved in regulating reproduction. FSH and LH are secreted by the basophilic cells of the anterior pituitary in response to the Gonadotropin-releasing hormone (GnRH) produced by the hypothalamus. The release of GnRH from the hypothalamus regulates the production of gonadotropins in the pituitary and these gonadotropins are responsible for gonadal development and growth in vertebrates. In addition to the hypothalamic GnRH (also called GnRH1 or GnRH-I), many vertebrate species have been found to express other GnRH forms.