GHRP-6 functions as a synthetic ghrelin mimetic by binding to the growth hormone secretagogue receptor (GHS-R1a) in the pituitary gland and hypothalamus[1][12]. This activation triggers acute, pulsatile growth hormone release from somatotroph cells while simultaneously reducing somatostatin’s inhibitory brake on GH secretion[3]. Unlike continuous GH administration, GHRP-6 maintains physiological feedback controls—as GH and IGF-1 levels rise, endogenous somatostatin increases to prevent excessive elevation, keeping GH pulses within normal physiologic ranges[5]. Beyond its endocrine effects, GHRP-6 exhibits cytoprotective properties through interactions with the CD36 receptor on immune and muscle cells[2][13]. This secondary pathway activates cell-survival signaling cascades (such as PI3K/Akt) that help protect tissues from oxidative stress and inflammation, explaining many of GHRP-6’s observed tissue-protective benefits in preclinical models including cardioprotection, neuroprotection, and anti-fibrotic effects[2][14].
