Selective GHS-R (ghrelin receptor) agonist — synthetic pentapeptide (Aib-His-D-2-Nal-D-Phe-Lys-NH₂) First GHRP-receptor agonist with selectivity comparable to GHRH in published research CAS 170851-70-4 For in vitro GH secretagogue research only
For laboratory research use only. Not for human or veterinary consumption. SKU IP10.
| Sequence | Aib-His-D-2-Nal-D-Phe-Lys-NH₂ |
| Molecular Formula | C38H49N9O5 |
| Molecular Weight | 711.85 g/mol |
| CAS Number | 170851-70-4 |
| PubChem CID | 9831659 |
| Purity | Research-grade |
| Form | Lyophilized powder |
| Quantity | 10mg per vial |
Ipamorelin binds to the growth hormone secretagogue receptor type 1a (GHS-R1a), a G protein-coupled receptor expressed primarily in anterior pituitary somatotrophs. The binding triggers a phospholipase C-mediated signaling cascade: IP3/DAG release, intracellular calcium mobilization, and protein kinase C (PKC) activation, culminating in growth hormone exocytosis. EC50 has been measured at 1.3 nmol/L in rat pituitary cell assays, with peak GH response occurring at approximately 40 minutes post-administration and a circulating half-life of approximately 2 hours (Gobburu et al., Pharmaceutical Research, 1999). What distinguishes ipamorelin from earlier GHS-R agonists (hexarelin, GHRP-6, GHRP-2) is its signaling selectivity. While those compounds activate GHS-R1a and also engage other pathways that elevate cortisol and prolactin, ipamorelin produces minimal cross-reactivity at GH-releasing concentrations. This selectivity makes it a valuable tool for researchers studying isolated GHS-R1a-mediated somatotroph activation without confounding adrenocorticotropic or lactotropic effects (Sinha et al., Transl Androl Urol, 2020; PMC7108996).
The published literature on ipamorelin extends well beyond somatotroph activation. Svensson et al. examined its effects in bone mineral density studies using dual-energy X-ray absorptiometry (DEXA) and peripheral quantitative computed tomography (pQCT) in murine models, documenting changes in cortical and trabecular bone parameters (Svensson et al., The Journal of Endocrinology, 2000). Greenwood-Van Meerveld et al. investigated ipamorelin in postoperative gastric dysmotility models, where GHS-R1a agonism was associated with effects on gastric emptying rate and smooth muscle contractility (J Exp Pharmacol, 2012; PubMed 27186124). Additional research contexts include the study of GHS-R1a constitutive activity (the receptor signals at approximately 50% of maximal capacity even without ligand binding), inverse agonism, and biased signaling — areas where ipamorelin serves as a reference agonist for characterizing receptor pharmacology (Holst et al., Molecular Endocrinology, 2003; PubMed 12893882).
Ipamorelin (GHS-R1a agonist) and CJC-1295 (GHRH receptor agonist) target different receptors within the same somatotropic axis. The published literature routinely examines these compounds together for dual-pathway somatotroph activation studies, as the two receptor systems converge on complementary intracellular signaling mechanisms in pituitary somatotrophs. Heritage Labs USA offers the CJC-IPA blend for researchers investigating this paired approach.
Every Heritage Labs compound is manufactured to research-grade standards and shipped in protective packaging.
For laboratory research use only. Not for human or veterinary use.