Melanotan-2 (MT-2)

What Is Melanotan-2?

Melanotan-2 (MT-2) is a synthetic analog of alpha-melanocyte-stimulating hormone (α-MSH) developed at the University of Arizona in the 1990s. It is a non-selective melanocortin receptor agonist, binding to MC1R through MC5R, which accounts for its broad range of observed effects including skin pigmentation, sexual arousal, appetite suppression, and fat metabolism.

MT-2 was originally developed as a potential preventive agent against skin cancer by stimulating the body’s natural tanning response without UV exposure. During clinical trials, researchers discovered significant secondary effects on sexual function and appetite, leading to the development of PT-141 (Bremelanotide) as a more selective derivative targeting sexual dysfunction specifically.

Mechanism of Action

Melanogenesis (MC1R)

MT-2 binds to melanocortin-1 receptors on melanocytes, stimulating eumelanin production independently of UV exposure. This increases skin pigmentation through the same biochemical pathway as natural tanning but without requiring DNA-damaging ultraviolet radiation to initiate the process.

Sexual Function (MC3R/MC4R)

Activation of MC3R and MC4R in the hypothalamus triggers dopaminergic and oxytocinergic signaling cascades involved in sexual arousal and desire. This central mechanism works in both male and female subjects, influencing libido at the neurological level rather than through peripheral vascular effects.

Appetite Regulation (MC4R)

MC4R activation in the hypothalamic arcuate nucleus and paraventricular nucleus modulates appetite-regulating neuropeptides. MT-2 reduces expression of orexigenic signals (appetite-stimulating) while enhancing anorexigenic pathways, resulting in decreased food intake in research models.

Lipolysis (MC5R)

MC5R activation influences lipid metabolism and fatty acid oxidation. Research suggests MT-2 may promote preferential fat utilization, though this effect is less pronounced than its melanogenic and sexual function activity.

Research Applications

• Melanogenesis – UV-independent tanning response and photoprotection research
• Sexual dysfunction – Libido and arousal studies in both male and female models
• Appetite regulation – MC4R-mediated satiety signaling and food intake reduction
• Body composition – Investigating melanocortin effects on fat metabolism and lipolysis
• Skin cancer prevention – Protective melanin stimulation without UV DNA damage
• Melanocortin receptor pharmacology – Non-selective agonist for receptor subtype characterization

Dosing Protocols

All protocols are for research reference only. Consult a qualified medical professional before use.

Preparation & Storage

Reconstitution

Supplies: peptide vial, bacteriostatic water, insulin syringes (29–31 gauge), alcohol swabs.

1. Clean both vial tops with alcohol swabs and let dry
2. Draw 2 mL of bacteriostatic water into the syringe
3. Insert needle into peptide vial at an angle against the glass wall
4. Let water run slowly down the side – never squirt directly onto powder
5. Gently swirl until fully dissolved – never shake
6. Solution should be clear – discard if cloudy or contains particles

Concentration: 10 mg in 2 mL = 5,000 mcg/mL

Storage

• Unreconstituted: Room temp or refrigerated, stable up to 24 months
• Reconstituted: Refrigerate at 2–8°C (36–46°F), use within 4–6 weeks
• Protect from direct sunlight and heat
• Do not freeze reconstituted solution

Cycling

Typical research cycle: Loading: 2–4 weeks. Results generally reported within 3–7 days.