PT-141 (Bremelanotide)

PT-141 is a cyclic heptapeptide lactam and a potent, non-selective melanocortin receptor agonist, specifically targeting the MC1R and MC4R subtypes. Unlike peripheral vasodilators, PT-141 acts centrally within the hypothalamus to modulate neuronal pathways involved in sexual arousal and motivation. It triggers the release of dopamine and suppresses serotonin-mediated inhibition, thereby facilitating the pro-erectile and pro-libido pathways without affecting blood pressure significantly. Research applications extend beyond sexual dysfunction to include studies on melanogenesis, inflammation modulation, and even feeding behavior, given the role of MC4R in energy homeostasis. Its unique mechanism of action allows researchers to investigate the central nervous system’s direct role in sexual response cycles. The peptide is highly sensitive to oxidation; thus, storage under inert gas and protection from light are critical for maintaining its cyclic structure and bioactivity.