Igtropin, also name as IGF1 LR3, is a polypeptide hormone about the same size as Insulin, or 70 amino acids. Igtropin is a highly anabolic hormone released primarily in the liver (but also in peripheral tissues) with the stimulus of Growth Hormone (GH). It is responsible for much of the anabolic activity of GH. Long R3 IGF-1 is found as …