GHRP-6

GHRP-6 (Growth Hormone Releasing Peptide 6) is a synthetic hexapeptide that stimulates growth hormone release by acting on the ghrelin/GHS receptor (GHS-R1a) at both pituitary and hypothalamic levels. It is one of the earliest GH secretagogues developed and remains widely used in research due to its well-characterized pharmacological profile. GHRP-6 is particularly noted for its potent appetite-stimulating properties, mediated through activation of ghrelin receptors in the arcuate nucleus, which trigger NPY/AgRP neuron activation and downstream orexigenic signaling. Beyond GH release, research has revealed GHRP-6's cytoprotective properties, including cardioprotective effects in ischemia-reperfusion models, hepatoprotective activity through reduction of oxidative stress and fibrosis markers, and neuroprotective effects in cerebral ischemia models. Studies have also explored its anti-inflammatory properties, with data showing reduction of TNF-α and IL-1β in various tissue injury models. The peptide's broad pharmacological profile makes it a versatile tool for studying GH axis physiology, appetite regulation, cardioprotection, and metabolic signaling.