Ipamorelin is a synthetic pentapeptide (Aib-His-D-2-Nal-D-Phe-Lys-NH2) that activates the ghrelin receptor (GHS-R1a) and was described in 1998 as a selective growth hormone secretagogue. Research includes rat, swine and cell studies and one published phase 2 trial.
Established: ipamorelin releases growth hormone through the GHRP (ghrelin) receptor pathway, shown in rat pituitary cells and with receptor antagonist studies [1]. Established in animals: unlike GHRP-6 and GHRP-2, it did not significantly raise ACTH or cortisol in swine and did not change FSH, LH, prolactin or TSH, which is why it was called selective [1]. Proposed: in rats, its effect on stomach emptying was attributed to ghrelin receptor action on cholinergic nerves [3].
| Study | Model | Reported result | Source |
|---|---|---|---|
| Ipamorelin as a selective GH secretagogue [1] | Other animal Rat primary pituitary cells; anesthetized rats; conscious swine | GH release EC50 1.3 nmol/L in rat pituitary cells (efficacy 85% of GHRP-6); in swine, no rise in ACTH or cortisol beyond GHRH. | Peer-reviewed Eur J Endocrinol 1998 |
| Ipamorelin and longitudinal bone growth [2] | Rat Rats given ipamorelin; bone length and body weight measured | Researchers reported increased longitudinal bone growth in rats. | Peer-reviewed Growth Horm IGF Res 1999 |
| Post-surgical gastric-emptying model [3] | Rat Rats after laparotomy with intestinal manipulation; isolated gastric fundus strips | Meal retained at 15 min fell from 78% (vehicle) to 52% with ipamorelin; nonsurgical controls 44%. Fundus contractility was restored ex vivo. | Peer-reviewed J Exp Pharmacol 2012 |
| Phase 2 post-surgical trial [4] | Human Phase 2, adults, randomized, double-blind, placebo-controlled, multicenter (2014) | Primary endpoint: time to tolerance of a standardized solid meal. Published. | Peer-reviewed Int J Colorectal Dis 2014 |
Human trials are listed for research context only; outcomes are reported in the linked publications. Animal and lab results do not establish effects in humans.
PureLab supplies Ipamorelin for laboratory research. Lot-specific certificates of analysis are posted on the product page as they are issued.
View research-grade Ipamorelin