Melanocortins: a research summary
Tide Front Supply Research Team · Apr 25, 2026 · 1 min read
MC1R through MC5R receptor pharmacology and the peptides commonly used to probe each.
The melanocortin system comprises five G-protein-coupled receptors (MC1R-MC5R) and a small set of endogenous ligands derived from POMC. Synthetic analogs targeting these receptors are useful tools for probing pigmentation, inflammation, energy balance, and reward circuitry.
Receptor distribution
- MC1R: melanocytes, immune cells.
- MC2R: adrenal cortex.
- MC3R, MC4R: central nervous system; appetite regulation.
- MC5R: exocrine glands, skeletal muscle.
Common research peptides
Melanotan-II is a non-selective agonist; PT-141 (bremelanotide) is more MC4R-selective. Selectivity matters because off-target activation produces confounding cardiovascular and pigmentation effects in animal models.
Handling
Most melanocortins are stable lyophilized but should be reconstituted in sterile bacteriostatic water and stored cold.