HGH and Penis Enlargement: What the Evidence Really Shows Prolonged Stimulation of Growth Hormone (GH) and Insulin Like Growth Factor I Secretion by CJC 1295, a Long Acting Analog of GH Growth Hormone Penis Growth: What the Evidence Actually Shows for Adult Men Ipamorelin and CJC 1295 are almost always discussed together in research circles, and the reason comes down to receptor pharmacology. The two peptides work through entirely different but complementary mechanisms that produce a Ipamorelin Vs Sermorelin: Decoding The Differences In Peptide Therapies