Ipamorelin is a synthetic pentapeptide growth hormone secretagogue and ghrelin-receptor agonist. Selective for growth hormone release with minimal effect on cortisol, prolactin, or ACTH at studied doses. Investigated in postoperative-ileus and gastric-motility models in addition to the original GH-secretagogue characterisation.
Definition
Ipamorelin is a synthetic pentapeptide (sequence Aib-His-D-2-Nal-D-Phe-Lys-NH2 in standard nomenclature, with the N-terminal aminoisobutyric acid residue and D-amino-acid substitutions providing protease resistance). The compound binds the growth hormone secretagogue receptor (GHSR-1a, the ghrelin receptor) on pituitary somatotrophs and on cells of the gastrointestinal tract, triggering G-protein-coupled receptor signalling and downstream growth hormone release.
The original Raun characterisation established ipamorelin as the first growth hormone secretagogue with high selectivity for GH release relative to other pituitary hormones (PMID 9849822). Selectivity vs cortisol, prolactin, and adrenocorticotropic hormone (ACTH) distinguishes ipamorelin from earlier-generation GH secretagogues that elevated all four pituitary outputs and limited their research utility for isolating GH-axis effects. Pharmacokinetic characterisation including nasal-absorption data was published in the same Novo Nordisk research-program window (PMID 9879640).
How ipamorelin is studied in peptide research
Beyond the original GH-secretagogue characterisation, ipamorelin has been examined as a ghrelin-receptor agonist in gastrointestinal-motility research. The Venkova rodent postoperative-ileus model documented prokinetic activity (PMID 19289567), with extension to gastric-dysmotility models in a related publication (PMID 27186127). Translation to human clinical investigation includes the Beck proof-of-concept trial in postoperative-ileus management after bowel-resection surgery (PMID 25331030). The compound’s structure-activity relationships in the broader peptidic-growth-hormone-secretagogue class are reviewed in Ferro and colleagues (PMID 26811125), and hybrid structures designed off the ipamorelin scaffold are characterised in the Ankersen and Hansen development series (PMID 9733495, PMID 11459660).
Ipamorelin is not currently approved for therapeutic use in humans or animals by any major regulator. The compound is supplied as research-grade lyophilised peptide for laboratory research applications only.
Related terms
- Growth hormone receptor
- Ghrelin / growth hormone secretagogue receptor (GHSR-1a)
- Somatotroph / pituitary
- GHRH (growth hormone-releasing hormone)
- IGF-1 / insulin-like growth factor 1
- Pentapeptide
Where ipamorelin appears in the Ronin catalog
- Ipamorelin 10mg — single-compound vial, lyophilized white powder under inert gas
- CJC-1295 + Ipamorelin blend — single-vial co-formulation pairing ipamorelin with the long-acting GHRH analogue CJC-1295
References
- Raun K et al. Ipamorelin, the first selective growth hormone secretagogue. Eur J Endocrinol 1998;139(5):552-561. [PMID 9849822]
- Johansen PB et al. Pharmacokinetic evaluation of ipamorelin and other peptidyl growth hormone secretagogues with emphasis on nasal absorption. Xenobiotica 1998;28(11):1083-1095. [PMID 9879640]
- Ankersen M et al. A new series of highly potent growth hormone-releasing peptides derived from ipamorelin. J Med Chem 1998;41(19):3699-3704. [PMID 9733495]
- Hansen TK et al. Highly potent growth hormone secretagogues: hybrids of NN703 and ipamorelin. Bioorg Med Chem Lett 2001;11(14):1915-1918. [PMID 11459660]
- Venkova K et al. Efficacy of ipamorelin, a novel ghrelin mimetic, in a rodent model of postoperative ileus. J Pharmacol Exp Ther 2009;329(3):1110-1116. [PMID 19289567]
- Beck DE et al. Prospective, randomized, controlled, proof-of-concept study of the Ghrelin mimetic ipamorelin for the management of postoperative ileus in bowel resection patients. Int J Colorectal Dis 2014;29(12):1527-1534. [PMID 25331030]
Glossary entries describe research-context use of peptide-research terminology. They do not constitute medical, veterinary, or clinical advice. Ipamorelin is sold strictly as a research-grade reagent for laboratory and bench research applications.