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Limited Research

Melanotan II

Skin, Hair & Beauty · ['MT-II', 'MT2', 'Melanotan 2']

A cyclic melanocortin-receptor agonist peptide studied for its activation of melanocortin signaling and the melanogenesis pathway.

🔬 Research use only — not for human or veterinary use. K4 Elite does not provide dosing instructions.
Molecular Formula
C50H69N15O9
Molecular Weight
1024.2 g/mol
PubChem
CID 92432 ↗
Research Level
Limited Research
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Melanotan II chemical structure

Melanotan II is a synthetic cyclic heptapeptide analog of alpha-melanocyte-stimulating hormone (alpha-MSH). It is a non-selective agonist across melanocortin receptor subtypes and has served as a research tool for studying the melanocortin system and the biology of melanogenesis.

Because of its broad melanocortin-receptor activity, it has been investigated in laboratory studies of pigmentation pathways as well as central melanocortin signaling. It is not an approved drug, and its research profile is more limited and preliminary than the closely related, approved compound bremelanotide.

Scientific interest centers on the pharmacology of melanocortin-receptor activation rather than any applied use.

Melanotan II is a non-selective agonist at melanocortin receptors, including MC1R, MC3R, MC4R, and MC5R. Activation of MC1R on melanocytes stimulates the melanogenesis pathway through cyclic-AMP signaling and upregulation of tyrosinase, the rate-limiting enzyme studied in eumelanin synthesis.

Its activity at central MC3R and MC4R subtypes has also been examined in research on melanocortin neural circuits, reflecting the broad receptor engagement that distinguishes it as a research probe.

  • Investigation of MC1R activation and the melanogenesis (tyrosinase) pathway [1]
  • Characterization of non-selective melanocortin-receptor agonism across subtypes [2]
  • Study of central melanocortin MC3R/MC4R signaling in animal models [2]
  • Exploration of melanocortin pharmacology as a structural research tool [1]
  • Assessment of melanocortin-linked physiologic parameters in preclinical studies [2]
📋 How published studies were conducted — a research reference summarizing study designs from the literature. This is not usage, dosing, or administration guidance. K4 Elite does not provide dosing instructions; determining any research protocol is the sole responsibility of the qualified researcher.

Melanogenesis pathway (in vitro) [1]: Cell-culture studies exposed melanocytes to melanocortin agonists and measured tyrosinase activity and melanin content, characterizing MC1R-driven activation of the pigmentation pathway.

Receptor selectivity profiling (in vitro) [2]: Binding and functional assays measured agonist potency of Melanotan II across MC1R, MC3R, MC4R, and MC5R subtypes, establishing its non-selective profile.

Central melanocortin studies (rodent) [2]: Animal research administered melanocortin agonists and measured neural and physiologic endpoints associated with MC3R/MC4R circuits to probe central pathway effects.

Combinations examined in the research literature. Descriptive only — not a recommendation to combine compounds.

Alpha-MSHCompatible
Endogenous melanocortin agonist that Melanotan II structurally mimics at the receptor level.
PT-141 (Bremelanotide)Neutral
Closely related melanocortin agonist studied within the same pharmacologic class.
MC1R pathway modulatorsSynergistic
Compounds acting on the melanogenesis pathway studied alongside melanocortin agonism in models.
Antihypertensive agentsCaution
Melanocortin agonists can affect cardiovascular parameters, a theoretical research consideration.
  1. Hadley & Dorr, Melanotan II melanocortin agonist (Peptides)
  2. Dorr et al., Melanotan II clinical pharmacology (Life Sci)
  3. PubChem CID 92432 (Melanotan II)
What is Melanotan II?
It is a synthetic cyclic analog of alpha-MSH that acts as a non-selective agonist at melanocortin receptors, used as a research probe of melanocortin signaling.
What pathway does it activate?
Studies show it activates MC1R to engage the melanogenesis (tyrosinase) pathway and also engages central MC3R and MC4R subtypes.
How does it relate to PT-141?
Both are melanocortin-receptor agonists in the same structural class; Melanotan II has a more limited, preliminary research profile and is not an approved drug.
What research areas involve it?
Published work covers melanogenesis pathway biology, melanocortin receptor selectivity profiling, and central melanocortin circuit studies in animal models.
Is this offered for personal or cosmetic use?
No. This is a research-use-only reference. The material is not intended for human or veterinary use, diagnosis, treatment, or any cosmetic application.
Disclaimer: This profile summarizes published preclinical and laboratory research for reference only. It is not medical advice and makes no claim of safety or efficacy in humans. Determining any research protocol is the sole responsibility of the qualified researcher. Products are sold strictly for in-vitro research and have not been evaluated by the FDA.