Ipamorelin is a synthetic pentapeptide growth hormone secretagogue with the sequence Aib-His-D-2-Nal-D-Phe-Lys-NH2, developed as a selective agonist of the ghrelin receptor (GHSR-1a). It was designed to provide selective GH secretagogue activity with improved specificity compared to earlier compounds such as GHRP-6 and GHRP-2.
Ghrelin Receptor Agonism Research
Preclinical research has examined Ipamorelin's binding affinity and functional activity at the GHSR-1a receptor and its downstream signaling through Gq-protein coupled pathways in pituitary somatotroph cells.
Selectivity and Specificity Studies
A defining characteristic of Ipamorelin is its apparent selectivity for GH secretion over other pituitary hormones. Studies comparing its effects to GHRP-2 and GHRP-6 in rodent models have documented significantly attenuated effects on ACTH and cortisol release.
Somatotropic Axis Modulation Research
Research has examined Ipamorelin's downstream effects on GH pulse parameters and IGF-1 axis modulation in preclinical models, as well as its interactions with somatostatin-mediated GH inhibition.
• Raun K et al. (1998). Ipamorelin, the first selective growth hormone secretagogue. European Journal of Endocrinology, 139(5), 552–561.
