MT-2 (Melanotan 2 Acetate)

What is Melanotan II (MT-2)?

Melanotan II is a synthetic cyclic analogue of α-melanocyte-stimulating hormone (α-MSH), developed at the University of Arizona. It was originally researched as a tanning agent — a way to achieve protective melanin pigmentation without significant UV exposure. Subsequent research revealed additional effects through MC3R and MC4R activation, including appetite suppression and sexual arousal modulation.

Mechanism of Action

MC1R Agonism — Melanin Synthesis

MT-2 activates MC1R on melanocytes, triggering the synthesis of melanin (specifically eumelanin, the dark-brown form). This produces skin darkening that is enhanced by UV exposure but can occur with minimal UV — distinguishing it from conventional tanning that requires sustained sun exposure.

MC4R Agonism — Appetite Suppression and Sexual Function

MC4R activation in the hypothalamus produces the same effects as PT-141 (a structural derivative of MT-2): enhanced sexual arousal and appetite suppression. MT-2's broader receptor profile compared to PT-141 (which is more selective for MC3R/MC4R) accounts for its additional tanning effects via MC1R.

MC3R Agonism

MC3R activation contributes to energy balance regulation and may modulate inflammatory responses — additional mechanism dimensions relevant to metabolic and immunological research.

Key Research Findings

Tanning Efficacy

Clinical studies at the University of Arizona demonstrated significant skin darkening in fair-skinned individuals with MT-2 administration combined with moderate UV exposure — producing a tan equivalent to months of conventional sun exposure. Subjects with minimal natural tanning response showed the most dramatic effects.

UV Protection

Increased melanin density provides measurable photoprotection. Research estimates the UV protection benefit of MT-2-induced tanning at approximately SPF 2-4 additional protection — modest but measurable.

Appetite and Weight

MT-2's MC4R-mediated appetite suppression produces meaningful caloric intake reduction in research models, with body weight effects documented in animal studies. This appetite modulation is being studied in obesity and metabolic research contexts.

*For research use only. Not for human consumption.*