The decapeptide gonadotropin-releasing hormone (GnRH) is the master hormone regulating reproduction. GnRH is released from some 1000 neurons within the hypothalamus in a pulsatile manner. Hypothalamic GnRH gene expression occurs intermittently (in a pulsatile fashion). The primary target of hypothalamic GnRH is the anterior pituitary gonadotrope, which responds to stimulation by increasing the synthesis and secretion of the gonadotropins luteinzing hormone (LH) and follicle stimulating hormone (FSH), which in turn regulate gonadal development and function.