GHRP-6

GHRP-6 (Growth Hormone Releasing Peptide-6) is a synthetic hexapeptide composed of six amino acids (His-D-Trp-Ala-Trp-D-Phe-Lys-NH2) that potently stimulates growth hormone release by acting as an agonist at the growth hormone secretagogue receptor type 1a (GHS-R1a), the same receptor targeted by the endogenous hormone ghrelin. Developed in the 1980s, GHRP-6 was one of the first synthetic GH secretagogues identified and has been extensively used in research to study the GH axis. Unlike more selective secretagogues such as Ipamorelin, GHRP-6 also significantly stimulates appetite through ghrelin-mimetic activity and may elevate cortisol and prolactin levels at higher doses. GHRP-6 produces robust GH pulses, particularly when administered alongside GHRH analogues like CJC-1295, as the two peptides act synergistically through distinct receptor pathways. Research applications have included studies on muscle wasting, metabolic syndrome, wound healing, and neuroprotection. Its strong appetite-stimulating properties make it of particular interest in cachexia and underweight research models.