What Is GHRP-6?

Bowers et al. (Endocrine Reviews): Comprehensive characterization of GHRP-6 showing dose-dependent GH release in humans with peak response at 1-2mcg/kg IV. Established GHRP-6 as the prototype GH secretagogue.

Combined GHRP-6 + GHRH produces synergistic GH release 3-5x greater than either peptide alone, demonstrating distinct receptor mechanisms.

Berlanga et al.: GHRP-6 demonstrates significant cardioprotective effects in myocardial ischemia-reperfusion injury models, reducing infarct size and oxidative damage independent of GH release.

Study confirms GHRP-6 activates ghrelin receptors in the GI tract, increasing gastric emptying rate and appetite. Clinically relevant for cachexia/wasting conditions.

A 2026 preclinical study demonstrated that GHRP-6 attenuated myocardial tissue demise, reduced scarring, and improved left ventricle physiology in a rat model of myocardial infarction. Researchers found these effects may be mediated by upregulating pathways involved in antioxidant defenses and mitochondrial metabolic reprogramming.

A 2026 study demonstrated that GHRP-6 reduced neutrophilic alveolitis, improved alveolar-capillary permeability, and preserved lung parenchymal integrity in mice. Researchers found that the peptide limited collagen accumulation, suggesting potential pneumoprotective effects against acute lung injury and subsequent fibrosis.

A 2026 study found that orally administered salmon acylated ghrelin significantly increased food intake in common carp. The research demonstrated this orexigenic effect occurred locally via ghrelin receptors and sensory nerves rather than through systemic absorption.

A 2026 study demonstrated that intracerebroventricular injection of LEAP-2 significantly decreased food intake in broiler chickens. The research found that this hypophagic effect is mediated through interactions with ghrelin and cannabinoid receptors.

A 2025 study found that a self-assembling GHRP-6 peptide hydrogel enhanced the survival of renal tubular epithelial cells and reprogrammed their metabolism in a mouse model of acute kidney injury. The hydrogel demonstrated these effects by activating the mTOR-P70 pathway, offering insights into cellular protection.

A 2025 study demonstrated that aza-isotryptophan analogs of GHRP-6 exhibit promising CD36 receptor binding affinity and modulate inflammatory responses induced by the Toll-like receptor-2/6 heterodimer. Researchers also successfully characterized the peptide's beta-turn geometry using X-ray and NMR analyses.

A 2025 in vitro study found that adding 75 ng/ml of GHRP-6 to culture media significantly promoted nucleonic maturation and early polar body appearance in human oocytes. However, the peptide did not significantly improve cytoplasmic maturation or alter meiotic gene expression within 24 hours.

A 2025 study demonstrated that GHRP-6 maintained stable cortisol levels and enhanced circulating immunoglobulins in fish following immune stimulation. Researchers found the peptide modulated immune gene expression in a tissue-specific manner without inducing histological alterations.

A 2025 study demonstrated that a novel butyrylcholinesterase inhibitor induced antidepressant, pro-cognitive, and anti-anhedonic effects in a rat model of depression. Researchers found these effects outperformed escitalopram in cognitive and reward behaviors, primarily operating through the ghrelin-dopamine cascade.

A 2025 study in rats demonstrated that ferulic acid, the primary component of Danshen-Chuanxiong-Honghua, alleviated blood-brain barrier disruption, reduced brain edema, and suppressed proinflammatory factors following traumatic brain injury. The researchers found these effects were mediated by modulating the Ghrelin/GHSR pathway.

Downregulation of the ghrelin receptor GHSR reduced parasite survival and alleviated liver inflammation during Echinococcus granulosus infection, a 2025 preclinical study demonstrated. Researchers found that GHSR knockout in mice significantly decreased liver infection foci and shifted cytokine profiles toward an anti-inflammatory state.

Ghrelin treatment improved motor functions, preserved memory consolidation, and increased the long-term survival and proliferation of neuronal cells following experimental stroke, according to a 2025 study. Researchers found these pro-neuroregenerative effects promoted functional recovery in rats.

A 2025 study found that daily intravenous administration of CIGB-500, or GHRP-6, was well-tolerated in beagle dogs over 28 days. Researchers demonstrated that doses up to 2000 μg/kg/day produced only transient, non-adverse effects, establishing this as the no observable adverse effect level.

A 2025 study found that ghrelin potently suppresses water intake in seawater-acclimated eels without affecting arterial pressure. Researchers demonstrated this anti-dipsogenic effect is likely mediated through a novel ghrelin receptor, distinct from the mechanisms of atrial natriuretic peptide.

A 2025 study in rats demonstrated that ghrelin and GHRP-6 significantly attenuated both the hyperactivity and hypoactivity associated with acute nicotine withdrawal. These findings indicate that both peptides can modulate locomotor behavioral changes during early nicotine cessation.

A 2025 study demonstrated that intranasal delivery of GHRP-6, but not ghrelin or MK-0677, successfully engaged the brain's ghrelin signaling system in mice. The peptide increased food intake, activated arcuate nucleus neurons, and elevated serum growth hormone levels.