GHRP-6
Also known as Growth Hormone Releasing Peptide-6, SKF-110679, Hexapeptide GHRP
GHRP-6 is the original hexapeptide ghrelin-receptor secretagogue, historically important for pointing researchers toward ghrelin itself. A research profile of the first GHRP.
GHRP-6 is where the growth-hormone-releasing-peptide story starts. As one of the first synthetic secretagogues, it did something unusual: it was a working agonist of a receptor before that receptor's natural hormone was even known. The search for what GHRP-6 was mimicking helped lead to the discovery of ghrelin — which makes this small hexapeptide historically outsized.
This page treats GHRP-6 as the origin point of the secretagogue branch. Descriptive chemistry and research context only, with no outcome or dosing claims.
One of the earliest synthetic growth-hormone-releasing peptides: a hexapeptide agonist of the growth-hormone secretagogue receptor (GHS-R). Its discovery helped lead researchers to the endogenous ligand of that receptor — the hormone ghrelin — which is a large part of why GHRP-6 is historically significant.
The peptide that pointed to ghrelin
GHRP-6 acts on the growth-hormone secretagogue receptor, GHS-R. When it was studied, that receptor was an orphan — no known natural ligand. GHRP-6 and its relatives were the synthetic tools that helped researchers characterize the receptor, and the eventual identification of ghrelin as its endogenous hormone is one of the notable stories in the field.
That lineage explains the terminology used throughout this cluster: 'ghrelin mimetic' and 'GH secretagogue' describe the same mechanism, and GHRP-6 is the archetype of it — separate from the GHRH-receptor analogs like sermorelin and CJC-1295.
A distinct research signature: appetite
Among the GHRPs, GHRP-6 is the one most associated in the literature with appetite and hunger signaling — a direct reflection of its action on the ghrelin receptor, since ghrelin is the body's hunger hormone. Where later secretagogues like ipamorelin were developed toward selectivity, GHRP-6 is remembered for this broader, ghrelin-like profile.
That signature is a research context, not a promised effect: it describes what scientists have studied the peptide in relation to, and it is one of the clearest ways GHRP-6 is differentiated from GHRP-2 and hexarelin.
Structure and identification
GHRP-6 is a six-residue peptide that includes D-configured amino acids and an amidated C-terminus, so it does not map to a plain string of standard codes. Certificates are read by mass and by HPLC purity — a single dominant peak and a mass matching the hexapeptide are the basic checks. Verify each lot against its own batch number.
These are research areas the compound is associated with in the literature — not medical claims or intended uses.
Handling & storage
Supplied lyophilized. Stored sealed and cold; reconstituted with bacteriostatic water only as a protocol requires, then refrigerated. Handle per accepted laboratory practice.
Verify a certificate by lot →Common questions
It was one of the first synthetic agonists of the growth-hormone secretagogue receptor, and the effort to understand what it was mimicking helped lead to the discovery of ghrelin, the receptor's natural hormone.
Both act on the ghrelin receptor, but GHRP-6 is an early, less selective peptide noted for a broader profile including appetite signaling, whereas ipamorelin was developed to be a more selective agonist.
No — it is a ghrelin mimetic acting on the GHS receptor, on the secretagogue side of the family rather than the GHRH-analog side.
This monograph is a research-use reference. It describes composition and the contexts in which the compound has been studied — it is not medical advice, a description of effects, or a recommendation for use. Sold strictly for laboratory and research use; not for human or animal consumption.