GHRP-6 (Growth Hormone Releasing Peptide-6) is a synthetic hexapeptide and one of the earliest growth hormone secretagogues to be characterized. Its sequence, His-D-Trp-Ala-Trp-D-Phe-Lys-NH2, contains D-configured tryptophan and phenylalanine residues that confer metabolic stability and receptor activity. It acts as an agonist at the growth hormone secretagogue receptor (GHS-R1a), the same receptor targeted by endogenous ghrelin, and stimulates GH release through a pathway distinct from GHRH.
As a foundational compound in secretagogue research, GHRP-6 is widely used as a reference agonist for characterizing ghrelin-receptor signaling and GH secretory responses. Unlike the more selective later-generation peptides, GHRP-6 is noted in the literature for also stimulating appetite and, at higher exposures, modestly influencing ACTH, cortisol and prolactin in model systems. Supplied as a lyophilized powder for research use only.
His-D-Trp-Ala-Trp-D-Phe-Lys-NH2
Research use only — not for human or animal consumption. Per-batch documentation is provided with the material.
GHRP-6 was among the first synthetic peptides shown to release GH through a receptor distinct from the GHRH receptor, work that ultimately contributed to the identification of the growth hormone secretagogue receptor and its endogenous ligand ghrelin. In model systems it produces robust GH secretion and characteristic GHS-R-mediated effects on appetite.
Because of its well-documented pharmacology and non-selective secretagogue profile, GHRP-6 remains a standard positive-control and reference compound in studies dissecting ghrelin-receptor signaling and comparing secretagogue selectivity across the GHRP family.
GHRP-6 was developed in the 1980s from the earlier enkephalin-derived GH-releasing peptides described by Bowers and colleagues, and became a key tool in the research that led to the discovery of the growth hormone secretagogue receptor in the 1990s and ghrelin in 1999. It remains a widely referenced early-generation growth hormone releasing peptide.
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Cited literature refers to laboratory and preclinical research. GHRP-6 is supplied strictly for research use only and is not intended to diagnose, treat, cure, or prevent any disease.
