About Ipamorelin
Ipamorelin is a synthetic pentapeptide (Aib-His-D-2-Nal-D-Phe-Lys-NH₂) that acts as a growth hormone secretagogue. Unlike GHRH analogues, which act at the GHRH receptor, ipamorelin binds the growth hormone secretagogue receptor GHS-R1a — the same receptor targeted by endogenous ghrelin.
Its defining characteristic in the research literature is selectivity. Earlier GHS compounds such as GHRP-2 and GHRP-6 also engage pathways that raise cortisol, ACTH and prolactin in the models studied; ipamorelin shows markedly less of that crosstalk, which is why it is often chosen when an experiment needs somatotroph activation isolated from confounding endocrine signals.
Research Applications
Ipamorelin is used in research investigating GHS-R1a receptor binding and selectivity, pulsatile growth hormone release kinetics, comparative secretagogue pharmacology against GHRP-class peptides, and combination designs that pair a GHS-R1a agonist with a GHRH-receptor analogue to study complementary pituitary pathways.