Ipamorelin (Growth Hormone Secretagogue)

Ipamorelin is a 5-amino acid selective growth hormone secretagogue and ghrelin mimetic that exhibits the highest GH specificity of any growth hormone-releasing peptide (GHRP) characterized to date. It binds the growth hormone secretagogue receptor (GHSR-1a) with an EC50 of 1.4 nM, potently stimulating pulsatile GH release while demonstrating minimal effect on cortisol, prolactin, or ACTH levels in preclinical models. This exceptionally clean pharmacological profile — free of the off-target hormonal perturbations common to other GHRPs — has established Ipamorelin as the gold standard compound for selective GH axis research and somatotroph signaling investigations.

Key Research Findings:

• In vitro receptor binding assays established an EC50 of 1.4 nM at GHSR-1a, confirming potent and selective ghrelin receptor engagement
• Rodent studies demonstrated robust, dose-dependent GH release without statistically significant elevations in cortisol, prolactin, or ACTH
• Preclinical head-to-head comparisons showed superior GH selectivity over GHRP-6 and GHRP-2, which both elevate cortisol and prolactin at equipotent GH-releasing doses
• Pharmacological profiling in animal models confirmed preservation of physiological GH pulsatility patterns, unlike continuous GH infusion paradigms

For laboratory and research use only.