GHRP-2

Mechanism of Action

GHRP-2 is a synthetic agonist of the growth hormone secretagogue receptor (GHS-R1a), the same receptor activated by the endogenous hormone ghrelin. By binding to GHS-R1a on pituitary somatotropes, GHRP-2 stimulates the release of growth hormone in a pulsatile manner, acting through a pathway distinct from but synergistic with growth hormone-releasing hormone (GHRH). GHRP-2 also directly activates GHS-R1a receptors on peripheral tissues including skeletal muscle, where it exerts direct anti-catabolic effects independent of GH release. Key Pathways: GHS-R1a receptor activation on pituitary somatotropes → GH release, Synergistic amplification of GHRH signaling for enhanced GH secretion, Direct GHS-R1a activation on myocytes → suppression of ubiquitin ligases (Atrogin-1, MuRF1), IGF-I axis stimulation secondary to GH release, Modulation of inflammatory mediators (TNF-alpha reduction) in peripheral tissues The pituitary GHS-R1a activation explains GHRP-2's ability to reliably stimulate GH pulses in humans, with effects observed within 60 minutes of administration. The direct action on muscle tissue—independent of GH—helps explain observed muscle-protective effects in catabolic states. The orexigenic (appetite-stimulating) effect is mediated through the same ghrelin receptor pathway in hypothalamic feeding centers.

Common Dose Reference Ranges

Educational reference ranges only — discuss actual dosing with a qualified healthcare provider.

Full GHRP-2 protocols — frequency, timing, cycle length, reconstitution & research