What Is Ipamorelin Nasal Spray and How Is It Used in Preclinical Research? Ipamorelin is a pentapeptide growth hormone secretagogue (GHS) belonging to the growth hormone-releasing peptide (GHRP) family. Structurally characterized as Aib-His-D-2-Nal-D-Phe-Lys-NH₂, ipamorelin was specifically engineered to selectively activate the GH secretagogue receptor type 1a (GHS-R1a) without significantly...