Melanotan II
Melanotan II (MT-II) is a synthetic cyclic heptapeptide analogue of α-melanocyte-stimulating hormone (α-MSH), an endogenous neuropeptide derived from the proopiomelanocortin (POMC) precursor protein. ...
Certificate of Analysis included with every order.
Technical Specifications
| Purity | ≥98% |
|---|---|
| Form | Lyophilized Powder |
| Storage | -20°C |
About This Peptide
Melanotan II (MT-II) is a synthetic cyclic heptapeptide analogue of α-melanocyte-stimulating hormone (α-MSH), an endogenous neuropeptide derived from the proopiomelanocortin (POMC) precursor protein. Structurally, Melanotan II is characterized by a lactam bridge between the lysine and aspartic acid residues of its core sequence, conferring enhanced metabolic stability and receptor affinity relative to the native linear peptide. Supplied here as a lyophilized powder of ≥98% purity, this compound is intended exclusively for laboratory and preclinical research settings.
Within the broader melanocortin system, Melanotan II serves as a non-selective agonist at the melanocortin receptor family, spanning MC1R through MC5R subtypes. The melanocortin system regulates a remarkably diverse array of physiological processes in mammalian biology, including pigmentation, energy homeostasis, inflammatory signaling, and neuroendocrine function. Because of this receptor promiscuity, Melanotan II has become a widely referenced pharmacological tool for dissecting melanocortin receptor biology in vitro and in animal models, enabling researchers to probe pathway crosstalk and downstream signaling cascades with a well-characterized ligand.
The compound's research history spans several decades, beginning with structure–activity relationship (SAR) studies at the University of Arizona aimed at identifying stabilized α-MSH analogues. These investigations established Melanotan II as a benchmark scaffold in peptide medicinal chemistry and receptor pharmacology. Its cyclic architecture, resistance to proteolytic degradation compared with linear α-MSH, and high binding affinity across multiple MC receptor subtypes make it a valuable reference agonist for comparative studies. Researchers investigating central and peripheral melanocortin signaling, neuropeptide receptor pharmacology, and metabolic regulation continue to employ Melanotan II as a standard tool compound in their experimental designs.
Pepitiva Biolabs supplies Melanotan II (internal code: Melanotan II) as a lyophilized powder stored at −20 °C to preserve structural integrity. All material is provided for research use only and is not intended for human or veterinary therapeutic application.
Research Applications
≥98% purity. Lyophilized Powder. Storage: -20°C. For research purposes only.
Mechanism of Action
Melanotan II exerts its effects primarily through agonistic binding at G protein-coupled melanocortin receptors (MCRs), with documented activity at MC1R, MC3R, MC4R, and MC5R subtypes. Upon receptor engagement, Melanotan II promotes coupling to Gαs proteins, leading to adenylyl cyclase activation, elevated intracellular cyclic AMP (cAMP) levels, and subsequent activation of protein kinase A (PKA) signaling cascades. The resulting phosphorylation events modulate transcription factor activity—most notably CREB (cAMP response element-binding protein)—and downstream gene expression programs relevant to pigmentation (e.g., MITF, tyrosinase induction at MC1R) and energy balance circuitry (e.g., hypothalamic MC4R-mediated pathways).
At MC4R, which is abundantly expressed in hypothalamic nuclei, Melanotan II–driven cAMP signaling intersects with leptin and insulin receptor pathways, making it a useful probe for studying central energy homeostasis networks in rodent models. MC3R activation by Melanotan II has been investigated in the context of peripheral and central feedback loops governing adiposity and autonomic tone. Additionally, MC1R-mediated signaling in melanocytes involves PKA-dependent phosphorylation of MITF and upregulation of melanogenic enzymes, providing a well-characterized in vitro model for pigmentation biology. The compound's capacity to activate multiple receptor subtypes simultaneously allows researchers to study receptor convergence, functional selectivity, and potential allosteric interactions within the melanocortin system.
Research Applications
Melanotan II is employed across a range of preclinical and in vitro research paradigms that require a potent, metabolically stable melanocortin receptor agonist. Representative research application areas include:
- Melanocortin receptor pharmacology: Characterization of MC1R–MC5R binding kinetics, selectivity profiling, and competitive displacement assays using radiolabeled or fluorescent ligands in recombinant cell-based systems.
- Pigmentation pathway research: Investigation of melanogenesis regulation in cultured melanocytes, including MITF transcription factor activation, tyrosinase expression, and eumelanin/phaeomelanin switching at MC1R.
- Energy homeostasis modeling: Preclinical rodent studies examining hypothalamic MC3R/MC4R-mediated modulation of food intake, body weight, and metabolic rate as part of POMC/AgRP circuit analyses.
- Neuropeptide signaling studies: cAMP reporter assays and phosphoproteomic profiling downstream of melanocortin receptor activation in neuronal and neuroendocrine cell lines.
- Structure–activity relationship (SAR) benchmarking: Use of Melanotan II as a reference agonist scaffold for comparative evaluation of novel cyclic and linear α-MSH analogues in peptide drug discovery programs.
- Inflammatory and immune signaling research: Exploration of MC1R and MC3R roles in modulating cytokine production and inflammatory mediator release in macrophage and immune cell culture models.
Storage & Handling Guidelines
Proper storage and handling are essential to maintain peptide integrity and ensure reliable research results. All Pepitiva Biolabs peptides are supplied as lyophilized (freeze-dried) powder, which provides excellent long-term stability when stored correctly. Store lyophilized peptides at -20°C for long-term storage or 2-8°C for short-term use. Once reconstituted, peptide solutions should be stored at 2-8°C and used within the timeframe specified in the product documentation. Always use sterile bacteriostatic water for reconstitution and handle peptides in a clean laboratory environment to prevent contamination. Avoid repeated freeze-thaw cycles, as thermal stress can cause peptide degradation and loss of biological activity.
Quality Control & Certification
This product is manufactured under strict quality control protocols and has been verified through comprehensive analytical testing. Each batch undergoes reverse-phase HPLC analysis for purity determination and electrospray ionization mass spectrometry (ESI-MS) for molecular identity confirmation. A detailed Certificate of Analysis (COA) is available for download, documenting purity percentage, molecular weight verification, appearance, and recommended storage conditions. Pepitiva Biolabs maintains batch-level traceability from synthesis through delivery, ensuring complete transparency and quality assurance for your research.
Frequently Asked Questions
Is this product approved for human use?
No. This product is intended exclusively for in vitro scientific research and laboratory use. It is not approved for human or veterinary use, not intended for diagnostic or therapeutic purposes, and should not be administered to humans or animals under any circumstances.
How do I reconstitute this peptide?
Add sterile bacteriostatic water slowly to the vial, directing the stream against the glass wall rather than directly onto the lyophilized powder. Gently swirl the vial until the powder is fully dissolved — do not shake vigorously. The recommended reconstitution volume depends on your desired concentration. Refer to the product documentation for specific guidance.
Can I get a Certificate of Analysis (COA)?
Yes. A Certificate of Analysis is included with every order and is also available for download from the product page. The COA documents HPLC purity, mass spectrometry identity confirmation, batch number, production date, and storage recommendations.
For research use only. Not for human consumption.