Melanotan 2 Acetate

The idea behind melanotan 2 was sun protection without the sun: in the 1980s researchers at the University of Arizona were looking for a molecule that triggers melanin formation without UV radiation, so that pigment could be studied as a protective factor. The outcome was a cyclic heptapeptide modelled on alpha-melanocyte-stimulating hormone, known today simply as MT-2.

Receptor profile: MT-2 does not bind selectively but engages MC1R, MC3R, MC4R and MC5R.

• Through MC1R on melanocytes the signal runs via cAMP to tyrosinase, eumelanin production rises and the skin darkens in research models.
• MC3R and MC4R sit centrally. This is where the hypothalamic axis, appetite and energy balance, and the melanocortin-driven sexual response meet.
• Exactly this broad profile separates MT-2 from melanotan 1 (MC1R only) and PT-141 (focus on MC4R).

Human data: the first pilot study in humans appeared in Life Sciences in 1996. Five low subcutaneous doses were enough for two of the three subjects to show a measurable gain in pigmentation, accompanied by mild nausea and spontaneous erections. Bioavailability after subcutaneous dosing is high.

A 2021 review summarises what the alpha-MSH/MC1R axis does beyond pigmentation, and a classic 1994 paper mapped the distribution of the MC4 receptor in neuroendocrine and autonomic circuits.

You will find melanotan 2 here strictly as a research compound. What you read sums up the evidence and is not a guide to use.

Because MT-2 engages several receptors, the range of possible effects is broader than with melanotan 1:

• Nausea, especially at the start, is the most commonly documented side effect.
• The skin darkens markedly, as do moles and freckles. Changes in moles are treated as a warning sign in the literature.
• Spontaneous erections through central MC4R activation were already described in the 1996 pilot study.
• Since MC4R helps regulate appetite, the literature reports altered appetite patterns.
• Flushing of the face is common, as is redness or tenderness where the needle went in.

This summary is no substitute for medical advice.

• Evaluation of melanotan-II, a superpotent cyclic melanotropic peptide in a pilot phase-I clinical study - the 1996 pilot study with measurable pigmentation in two of three subjects.
• The alpha-MSH/MC1R interaction: A driver of pleiotropic effects beyond pigmentation - 2021 review of what the MC1R axis does apart from skin colour.
• Localization of MC4-R in neuroendocrine and autonomic control circuits - mapping of the central MC4 receptor from 1994.