Melanotan II Research Guide: Melanocortin Receptor Studies

<p>Melanotan II (MT-II) is a synthetic cyclic heptapeptide analog of alpha-melanocyte-stimulating hormone (α-MSH), developed in the 1980s at the University of Arizona. Melanotan II acts as a non-selective agonist at multiple melanocortin receptors (MC1R, MC3R, MC4R, MC5R), making it a widely used research tool for studying the melanocortin system across multiple biological pathways.</p><h2>Molecular Profile</h2><p>Sequence: Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2 | MW: 1024.2 g/mol | CAS: 121062-08-6</p><h2>Melanocortin Receptor System</h2><p>The melanocortin system comprises five G-protein coupled receptors (MC1R–MC5R) with distinct expression patterns and biological roles:</p><ul><li>MC1R — expressed in melanocytes; regulates pigmentation pathway</li><li>MC3R — expressed in brain and gut; studied for energy homeostasis research</li><li>MC4R — expressed extensively in CNS; extensively studied for feeding behavior and energy balance</li><li>MC5R — expressed in exocrine glands; studied for sebum and exocrine function</li></ul><p>Melanotan II&#x27;s non-selective agonism across multiple MCRs makes it a useful tool for studying receptor-mediated signaling pathways while also requiring researchers to account for multi-receptor contributions to observed effects.</p><p>↗ Hadley ME, Dorr RT. (2006). Melanocortin peptide therapeutics: historical milestones. Peptides. PubMed ID: 16872718</p><h2>Research Applications</h2><ul><li>Melanocortin receptor pharmacology and binding studies</li><li>Pigmentation pathway research via MC1R activation models</li><li>Energy balance and feeding behavior research (MC4R studies)</li><li>Sexual behavior neuroendocrinology research in animal models</li><li>Comparative studies vs. selective MCR agonists</li></ul><p>Q: Is Melanotan II the same as Melanotan I?</p><p>A: No. Melanotan I (afamelanotide) is a linear analog primarily selective for MC1R. Melanotan II is a cyclic analog with non-selective activity across MC1R, MC3R, MC4R, and MC5R.</p><p>Q: Is Melanotan II FDA approved?</p><p>A: No. Melanotan II is not FDA approved for any indication and is sold exclusively for in-vitro laboratory research purposes.</p><p>Related: Melanotan II Product → | PT-141 Research Guide → | Kisspeptin Research Guide → | Melanocortin Products →</p>