Melanotan 2 is a cyclic lactam analogue of alpha-melanocyte-stimulating hormone (α-MSH) developed at the University of Arizona in the late 1980s. Its cyclized backbone confers markedly greater potency and metabolic stability than the native hormone. Research has examined its non-selective activity across the melanocortin receptor family, with published work spanning melanogenesis, appetite regulation, and central nervous system signaling in cell culture and rodent models.
Melanotan 2 is a cyclic lactam analogue of alpha-melanocyte-stimulating hormone (α-MSH) developed at the University of Arizona in the late 1980s. Its cyclized backbone confers markedly greater potency and metabolic stability than the native hormone. Research has examined its non-selective activity across the melanocortin receptor family, with published work spanning melanogenesis, appetite regulation, and central nervous system signaling in cell culture and rodent models.
Melanotan 2 (Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH₂) is supplied strictly as a reference material for in vitro and preclinical investigation. All characterization data described here is drawn from peer-reviewed literature and laboratory analysis; nothing herein constitutes a claim of clinical effect in humans.
The following domains summarize directions explored across published studies and laboratory models. Each reflects observations reported in rodent models, in vitro systems, or the peer-reviewed record.
Melanotan 2 is a widely used research tool for MC1R activation. Studies in melanocyte cultures and rodent models have documented increased tyrosinase activity and eumelanin synthesis following exposure, making it a reference agonist in pigmentation biology.
Research in rodent models has examined Melanotan 2 as an MC4R agonist in studies of food intake and energy balance, with observed reductions in feeding behavior that helped establish the melanocortin system as a regulator of appetite.
Published studies have used Melanotan 2 to probe MC3R and MC4R signaling in the central nervous system. This literature contributed directly to the development of the more selective analogue bremelanotide (PT-141).
Investigators have examined whether melanocortin-driven eumelanin accumulation alters cellular response to ultraviolet exposure, using Melanotan 2 in cell culture and animal models of UV-induced DNA damage.
Mechanistic steps below are hypothesized from in vitro assays and animal-model data reported in the literature. They describe biochemical interactions observed under controlled experimental conditions.
Melanotan 2 acts as an agonist at MC1R, MC3R, MC4R, and MC5R with limited discrimination between subtypes. This broad profile makes it a useful comparator against subtype-selective analogues in receptor pharmacology studies.
A lactam bridge between the Asp and Lys residues constrains the peptide backbone into a conformation that resists enzymatic degradation, producing substantially longer duration of action than linear α-MSH.
MC1R binding activates adenylyl cyclase and raises intracellular cAMP, which promotes MITF expression and tyrosinase transcription — the rate-limiting step in melanin biosynthesis documented in melanocyte cultures.
Central MC3R and MC4R activation in hypothalamic nuclei modulates downstream neural circuits governing energy homeostasis and autonomic output, mechanisms characterized across multiple rodent research models.
| Amino Acid Sequence | Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH₂ |
|---|---|
| Molecular Weight | 1,024.2 g/mol |
| Molecular Formula | C₅₀H₆₉N₁₅O₉ |
| CAS Number | 121062-08-6 |
| Storage | −20°C long-term, 4°C short-term up to 4 weeks |
The following peer-reviewed references informed the research summaries on this page. Citations are provided for scientific context only.
This product is intended strictly for laboratory research purposes only. It is not a drug, food, cosmetic, or dietary supplement and is not intended to diagnose, treat, cure, or prevent any disease. It is not for human or animal consumption. All information presented is derived from published scientific literature and is provided for educational reference only. By purchasing, the buyer affirms they are a qualified researcher or institution and assume full responsibility for the safe and lawful handling of this material.