Growth Hormone Releasing Activity of Ghrelin

The isolation of ghrelin is one of the most important breakthroughs in the understanding of the regulatory mechanisms involved in the neuroregulation of growth hormone (GH) secretion for several reasons. It gives definitive proof of the existence of a GH Secretagogue (GHS)/GHS-receptor signaling system in the control of GH secretion. Although for many years it was dogma that GH secretion by the anterior pituitary gland was the net result of the antagonistic actions of growth hormone releasing hormone (GHRH) and somatostatin, now a new physiological model of the regulation of GH secretion involving GHRH, somatostatin and ghrelin must be developed. It opens up the possibility of gaining a greater insight into the physiopathological mechanisms involved in the alterations of somatotroph cell function and somatic growth. Finally, it will allow the development of new agonist and antagonist compounds that may well be useful in the treatment of different disease states.