Peptide Handbook
Specialized Peptides

Melanotan II

Pan-Melanocortin Receptor Agonist

Updated April 14, 2026

What is Melanotan II?

A cyclic heptapeptide analog of alpha-MSH that non-selectively activates MC1R through MC5R melanocortin receptors. Unlike MC1R-selective Melanotan I, MTII's pan-receptor profile produces simultaneous tanning (MC1R), appetite suppression (MC4R), sexual arousal (MC3R/MC4R), and potential cardiovascular effects. The cyclic lactam bridge (Asp-Lys) confers metabolic stability and enhanced receptor affinity compared to linear α-MSH.

Research Profile

Structure 7 amino acids, cyclic (~1,024 Da) — Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH₂
Targets MC1R, MC3R, MC4R, MC5R (pan-melanocortin)
Research Focus Melanocortin receptor pharmacology, melanogenesis, appetite, sexual function crosstalk
Reconstitution Bacteriostatic water — 1 mg/mL
Stability 21 days at 2–8°C
Key distinction: Pan-melanocortin agonist — simultaneous activation of MC1R through MC5R produces a unique multi-system pharmacology (skin, appetite, sexual, immune) that selective agonists cannot replicate.

Published Research

[1] Hruby VJ et al. Design of peptides, proteins, and peptidomimetics in chi space. Biopolymers 1997;43:219-266 — PubMed 9277134
[2] Dorr RT et al. Evaluation of melanotan-II, a superpotent cyclic melanotropic peptide in a pilot phase-I clinical study. Life Sci 1996;58:1777-1784 — PubMed 8637402
Research Use Only. All products sold by Lumen Peppers are intended solely for in vitro research and laboratory purposes. They are not drugs, supplements, or foods. Nothing on this page constitutes medical advice. Researchers are responsible for compliance with all applicable regulations. Last updated: April 14, 2026.

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