Peptide Database

Pentapeptide-18

Leuphasyl is a pentapeptide that acts as an enkephalin analog, binding to δ-opioid receptors on muscle cells and neuronal cells to modulate acetylcholine release and reduce muscle contraction. Often combined with Argireline in cosmetic formulations for a synergistic anti-wrinkle effect, studies show the combination outperforms either compound alone in reducing crow's feet and forehead lines.

MT-II · MT2

Melanotan II is a cyclic synthetic analog of α-MSH that non-selectively activates melanocortin receptors (MC1R–MC5R). It induces skin tanning (via MC1R), erectile function (via MC4R), and sexual arousal while also suppressing appetite. It was the precursor compound from which PT-141 was developed. Research continues despite regulatory concerns due to its broad receptor activity profile.

Alpha-Melanocyte-Stimulating Hormone · α-Melanotropin

α-MSH is an endogenous 13-amino-acid peptide derived from POMC (pro-opiomelanocortin). It activates MC1R to stimulate melanin production in skin, MC4R to suppress appetite and regulate energy expenditure, and MC3R/MC1R to exert potent anti-inflammatory effects. It is the parent compound from which many synthetic melanocortin analogs (Melanotan I, II, PT-141, KPV) were derived and remains a cornerstone of melanocortin pharmacology research.