Melanotan

Melanotan II – melanocortin receptor agonist for pigmentation tests

Melanotan II (MT-II) is a synthetic cyclic heptapeptide that is an agonist of melanocortin receptors (MCR) with a broad receptor profile. It is a research tool in experiments on the melanocortin system and pigmentation processes in cellular models. A substance intended exclusively for scientific research (Research Use Only) – it is not a medicinal product. Check out Melanotan II in the One Peptides offer.

See also the full section research peptides.

What is Melanotan II?

Melanotan II (MT-II) is a synthetic cyclic heptapeptide developed at the University of Arizona in the 1980s and 1990s by a team led by Professor Victor Hadley. It was designed as an analogue of alpha-melanocyte-stimulating hormone (alpha-MSH) with a cyclic structure that gives it greater metabolic stability.

Melanotan II has affinity for many subtypes of melanocortin receptors – MC1R, MC3R, MC4R and MC5R. This broad receptor profile causes MT-II to engage different signaling pathways depending on the target tissue – from melanocytes (MC1R) through hypothalamic neurons (MC3R, MC4R) to exocrine glands (MC5R). In cell models, activation of MC1R by MT-II leads to stimulation of the cAMP/PKA pathway and an increase in eumelanin synthesis.

Melanotan II is a valuable tool in research on the melanocortin system, enabling analysis of the effects of simultaneous activation of multiple MCR receptor subtypes in various experimental models.

Melanotan variants available

The product is supplied with a Certificate of Analysis (CoA) covering HPLC and MS data. Detailed specifications, including structure, sequence and storage conditions, can be found on the product data sheet.

MELANOTAN II 10 mg — product characteristics

MELANOTAN II 10 mg in the form of a lyophilized product is a universal research product intended for experiments on the melanocortin system. Thanks to its broad receptor profile (MC1R, MC3R, MC4R, MC5R), Melanotan II is used both in studies of melanogenesis processes in melanocyte models and in experiments on melanocortin pathways in various tissues – melanocytes, nervous tissue and exocrine glands. The grammage of 10 mg allows for numerous experimental series and multiple repetitions.

The cyclic structure of MT-II ensures high metabolic stability, which is an important advantage in longer research protocols. The freeze-dried form guarantees stability during storage and allows for precise measurement of the solution after reconstitution in sterile water or an appropriate buffer.

How does Melanotan II differ from similar peptides?

Melanotan II vs Melanotan I (scientific context)

In the scientific literature, Melanotan II is often combined with Melanotan I (MT-I / afamelanotide) – a linear thirteen-peptide with selective affinity for the MC1R receptor. The fundamental difference lies in the selectivity profile: MT-I primarily activates the melanogenesis pathway in melanocytes via MC1R, while MT-II – thanks to its cyclic structure – binds to MC1R, MC3R, MC4R and MC5R, also engaging neuronal pathways in the hypothalamus. The cyclic structure of MT-II also gives it greater resistance to enzymatic degradation. Only Melanotan II is available in the One Peptides offer.

Melanotan II vs PT-141 (Bremelanotide)

PT-141 (Bremelanotide) is a direct derivative of Melanotan II — created by removing the C-terminal amide group from MT-II. While MT-II activates a broad spectrum of MCR receptors (MC1R, MC3R, MC4R, MC5R), PT-141 has preferential affinity for MC3R and MC4R. In animal models, PT-141 has no significant effect on melanogenesis (MC1R), and its activity is focused on melanocortin pathways in the central nervous system. Comparison of MT-II with PT-141 allows for the differentiation of peripheral (MC1R-dependent) from central (MC3R/MC4R-dependent) effects. See category PT-141

FAQ – Frequently asked questions

1. What is Melanotan II and how does it differ from Melanotan I?
Melanotan II (MT-II) is a synthetic cyclic heptapeptide that activates many subtypes of melanocortin receptors (MC1R, MC3R, MC4R, MC5R). In the scientific literature, it is often compared with Melanotan I – a linear peptide with selective affinity for MC1R. They differ in structure (cyclic vs linear), receptor selectivity and metabolic stability. Only Melanotan II is available in the One Peptides offer.

2. Is Melanotan II a medicinal product?
NO. Melanotan II offered by One Peptides is a substance intended exclusively for scientific research (Research Use Only). It is not a medicinal product, dietary supplement or food for consumption.

3. What are melanocortin receptors?
Melanocortin receptors (MC1R-MC5R) are a family of five G-protein-coupled receptors (GPCRs) activated by proopiomelanocortin (POMC)-derived peptides. They differ in tissue distribution and function: MC1R predominates on melanocytes, MC2R is an ACTH receptor in the adrenal glands, MC3R and MC4R are expressed in the CNS, and MC5R is expressed in exocrine glands.

4. How to store Melanotan II?
Freeze-dried Melanotan II should be stored at -20 degrees Celsius, in a dry place protected from light. After reconstitution, the solution should be divided into aliquots and frozen at -20 degrees Celsius. Repeated freezing and thawing cycles should be avoided. Detailed guidelines can be found on the product’s SDS card.

5. Is PT-141 a derivative of Melanotan II?
Yes. PT-141 (Bremelanotide) was formed as a metabolite of Melanotan II, after removal of the C-terminal amide group. It retains affinity for MC3R and MC4R receptors, but shows much less activity towards MC1R compared to MT-II. This structural relationship makes the comparison of MT-II with PT-141 an important tool in the study of receptor selectivity in the melanocortin system.

Quality and standards at One Peptides

Melanotan II in the One Peptides offer is subjected to rigorous quality control. Purity is verified by HPLC and identity is confirmed by mass spectrometry (MS). Each batch has a certificate of analysis (CoA) and a safety data sheet (SDS), available for download on the product page. Analytical standards ensure repeatability of results in laboratory conditions.