Melanotan II
Synthetic α-MSH Analog — Cyclic Heptapeptide
Melanotan II is a synthetic cyclic analog of alpha-melanocyte stimulating hormone (α-MSH), originally designed and synthesized at the University of Arizona in the 1980s. Created as a research tool for studying melanocortin receptor activation, it incorporates cyclization and D-amino acid substitutions to increase receptor binding affinity and metabolic stability. It occupies a foundational position in melanocortin research — its broad receptor activity enabled characterization of the MC1R–MC5R receptor family, and its unexpected MC4R-mediated effects led directly to the development of PT-141.
Why Researchers Study It
Melanotan II remains a reference compound in melanocortin research because of its non-selective receptor profile. It activates MC1R through MC5R with varying affinities, making it a valuable tool for studying the entire melanocortin receptor family. The compound illustrates how research tools designed for one purpose can generate discoveries in entirely different biological systems.
Melanocortin Receptor Characterization
Studies have documented Melanotan II's binding affinity across MC1R through MC5R, establishing quantitative dose-response relationships for the melanocortin receptor family.
Melanogenesis Research
Clinical research documented dose-dependent increases in melanin production, establishing the compound's role in MC1R-mediated pigmentation pathway studies.
MC4R-Mediated Pathway Discovery
Unexpected MC4R-mediated effects observed during research directly led to the development of PT-141 and opened an entirely new research direction.
Pharmacokinetic Profiling
Detailed studies have examined absorption, distribution, and metabolism of Melanotan II, providing quantitative bioavailability data that informed future melanocortin peptide design.
Research Timeline
8 milestones spanning 1980–2023
- Designed and synthesized as a superpotent cyclic α-MSH analog at University of Arizona (1980–1984)
- MC4R-mediated effects discovered, directly leading to PT-141 development (1998–2000)
- Historical milestones review published by Hadley & Dorr in Peptides (2006)
Related Learning
Guides, articles, and resources connected to this compound.
Melanocortin Receptors Explained
How the MC1R–MC5R receptor family mediates diverse physiological pathways.
Peptide Mechanisms Explained
Receptor binding, signaling cascades, and pathway interactions.
Complete Guide to Research Peptides
Comprehensive overview of the research peptide landscape.
How Peptides Work
Foundation guide covering peptide structure and signaling mechanisms.
Research Database
Searchable index of published research across all compounds.
Published Research
Selected citations from the published literature.
Hadley ME, Dorr RT. Melanocortin peptide therapeutics: historical milestones, clinical studies and commercialization. Peptides. 2006;27(4):921-930
Wessells H, et al. Melanocortin receptor agonists, penile erection, and sexual motivation. Int J Impot Res. 2000;12(Suppl 4):S74-S79
Explore Melanotan II
Research data, product specifications, and related kits.
Research Use Compliance
All information presented on this page references published preclinical research and is provided for educational and informational purposes only. These products are intended for laboratory research use only. Not for human consumption. No statements on this page have been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.