GHRP-6

GHRP-6 (Growth Hormone Releasing Peptide-6) — hexapeptide ghrelin mimetic

GHRP-6 is a synthetic hexapeptide belonging to the first generation of growth hormone secretagogues (GHS). It acts as an agonist of the GHS-R1a receptor and is one of the earliest studied peptides from the GHRP family. In animal models, GHRP-6 shows strong stimulation of growth hormone release and a clear effect on eating behavior. The product is intended for research use only (Research Use Only) – it is not a medicinal product or a dietary supplement. Browse available GHRP-6 variants from One Peptides.

What is GHRP-6?

GHRP-6 (Growth Hormone Releasing Peptide-6), also known as SKF-110679, is a synthetic hexapeptide with the sequence His-D-Trp-Ala-Trp-D-Phe-Lys-NH2. It is one of the earliest peptides from the GHRP family – its synthesis and pharmacological characteristics date back to the 1980s, when Cyril Bowers and colleagues conducted pioneering research on substances that stimulate the release of growth hormone regardless of the GHRH pathway.

GHRP-6 acts as an agonist of growth hormone secretagogue receptor type 1a (GHS-R1a). This receptor was later identified as the endogenous ghrelin receptor. Binding of GHRP-6 to GHS-R1a on anterior pituitary somatotrophs triggers a signaling cascade involving phospholipase C, inositol triphosphate (IP3) and intracellular calcium mobilization, leading to degranulation and GH release.

In studies on animal models, GHRP-6 has a stronger effect on appetite stimulation than GHRP-2. This effect is associated with the activation of ghrelin pathways in the arcuate nucleus of the hypothalamus. GHRP-6 can also modulate cortisol and prolactin release to some extent in rodent models. The molecular weight of GHRP-6 is approximately 873 Da.

GHRP-6 variants available

The product is supplied with a Certificate of Analysis (CoA) confirming the purity and identity of the substance based on HPLC and MS analyses. Full analytical specifications are available on the product card.

Which GHRP-6 variant should you choose?

GHRP-6 is available from One Peptides in the form of a lyophilized product containing 5 mg of substance per vial. This number allows both preliminary pilot studies and protocol validation, as well as conducting experimental series including comparisons with other GH secretagogues (e.g. GHRP-2, Ipamorelin).

GHRP-6 in the form of lyophilisate shows good stability when stored at temperatures below -20 degrees Celsius. After reconstitution, the solution should be used immediately or divided into aliquots and frozen to preserve activity.

How does GHRP-6 differ from similar peptides?

GHRP-6 vs. GHRP-2

Both peptides are hexapeptides and GHS-R1a agonists, but they differ in their activity profiles in animal models. GHRP-6 stimulates appetite more strongly – this effect is clear in studies on rodents and is associated with more intense activation of orexigenic pathways in the hypothalamus. GHRP-2 is considered to be more selective for the GH axis, with less impact on feeding behavior. In terms of stimulation of GH release, both peptides show comparable effectiveness, but their side effect profiles differ, which is important when designing research protocols. See category: GHRP-2

GHRP-6 vs Ipamorelin

Ipamorelin is a new generation GHS peptide, designed for maximum selectivity towards the GH axis. In animal models, Ipamorelin has minimal effects on cortisol, prolactin and appetite levels, which distinguishes it from GHRP-6. GHRP-6, as a first-generation peptide, has a broader activity profile – in addition to GH stimulation, it also modulates other hormonal axes. The choice between these peptides in research protocols depends on whether the goal is to analyze the GH axis in isolation (Ipamorelin) or to observe a broader spectrum of effects (GHRP-6). See category: Ipamorelin

GHRP-6 vs CJC-1295

CJC-1295 is a GHRH analogue acting through the GHRH-R receptor – a completely different pathway than GHS-R1a activated by GHRP-6. CJC-1295 stimulates GH release in a pulsatile manner, maintaining the natural rhythm of secretion, while GHRP-6 causes a fast, intense peak of GH release. The scientific literature describes protocols combining both peptides in studies on animal models – their mechanisms are complementary, which allows for the analysis of potential synergistic interactions at the level of the somatotropic axis. See category: CJC-1295

FAQ – Frequently asked questions

1. What is GHRP-6 and what is its history?
GHRP-6 is a synthetic hexapeptide that is one of the earliest developed growth hormone secretagogues. His research dates back to the 1980s and the pioneering work of Cyril Bowers. It acts as an agonist of the GHS-R1a receptor (ghrelin receptor) on pituitary somatotrophs.

2. How does GHRP-6 differ from natural ghrelin?
Ghrelin is an endogenous 28-amino acid peptide that requires acylation (modification with octanoic acid) for full activity. GHRP-6 is a synthetic hexapeptide with a different sequence that activates the same GHS-R1a receptor without the need for acylation. GHRP-6 shows higher stability in laboratory conditions than native ghrelin.

3. Is GHRP-6 a drug or supplement?
NO. GHRP-6 available at One Peptides is a substance intended exclusively for scientific research (Research Use Only). It is not a medicinal product, drug, dietary supplement or substance intended for any clinical use in humans or animals.

4. Why does GHRP-6 stimulate appetite in animal models?
The GHS-R1a receptor, on which GHRP-6 acts, plays a dual role in the body – it is involved in both the release of GH and the regulation of appetite through orexigenic pathways in the arcuate nucleus of the hypothalamus. GHRP-6 activates both of these pathways, with a stronger effect on appetite than in the case of GHRP-2.

5. How to store GHRP-6?
Freeze-dried GHRP-6 should be stored at a temperature below -20 degrees Celsius, in a tightly closed container, protected from light and moisture. After reconstitution, the solution should be used immediately or divided into aliquots and frozen. Avoid repeated freezing and thawing.

Quality and standards at One Peptides

Each batch of GHRP-6 in One Peptides undergoes multi-stage quality control. The purity of the peptide is confirmed by HPLC, and the molecular identity is verified by mass spectrometry (MS). Each product is accompanied by a Certificate of Analysis (CoA) with full analytical data and a Safety Data Sheet (SDS) containing information on storage conditions and handling of the substance.

Related research overview: differences between these secretagogues are discussed in GHRP-2 vs GHRP-6 differences in research.