GHRP-6

A synthetic hexapeptide (His-D-Trp-Ala-Trp-D-Phe-Lys-NH2, CAS 87616-84-0), one of the first growth-hormone-releasing peptides synthesized, derived from the endogenous opioid Met-enkephalin. Agonizes the ghrelin/GHS-R1a receptor to stimulate GH release and robustly increases appetite via parallel ghrelin-receptor signaling in hypothalamic feeding centers. Served as the scaffold from which GHRP-2, hexarelin, and ipamorelin were developed; remains a common research reference compound. Not FDA-approved.