Beyond Hunger: The Structure, Signaling, and Systemic Roles of Ghrelin Normal Physiology of ACTH and GH Release in the Hypothalamus and Anterior Pituitary in Man Endotext NCBI Bookshelf LEAP2: A novel regulator of food intake and body weight? Nature Reviews Gastroenterology & Hepatology What Is Ipamorelin and How Does It Compare vs HGH and Peptides Can Ipamorelin cause erectile dysfunction? 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