Ipamorelin is a pentapeptide. Five amino acids. That's it. But three of those five don't exist in nature. The sequence: Aib His D 2 Nal D Phe Lys, with a C terminal amide. Position 1 is aminoisobutyric acid the Normal Physiology of ACTH and GH Release in the Hypothalamus and Anterior Pituitary in Man Endotext NCBI Bookshelf Frontiers From the perspective of prolactin: a view on obesity ACTH (Adrenocorticotropic Hormone), Cushing's Syndrome Labpedia.net Frontiers Non Canonical Effects of ACTH: Insights Into Adrenal Insufficiency Hypothalamic Pituitary Adrenal (HPA) Axis: ACTH, Cortisol, Regulation and Functions TeachMePhysiology