PT-141 (Bremelanotide) | 20mg | 3ml

PT‑141 (also known as bremelanotide) is a synthetic cyclic heptapeptide melanocortin‑receptor agonist derived structurally from Melanotan II. It is produced by modifying the C‑terminus of the MT‑II scaffold — replacing the terminal amide with a hydroxyl group — yielding a related cyclic peptide with a distinct receptor‑selectivity profile while retaining the lactam‑bridged, enzymatically stable architecture of its parent compound. These properties make PT‑141 a well‑defined reference peptide for studying melanocortin signalling under controlled laboratory conditions.\n\nIn biochemical and cellular research systems, PT‑141 acts as an agonist at the centrally expressed melanocortin receptors MC3R and MC4R, with comparatively higher potency at MC4R and substantially reduced activity at MC1R relative to Melanotan II. This shift toward MC4R selectivity makes PT‑141 a useful tool for isolating MC4R‑mediated signalling — including G‑protein‑coupled cAMP and phospholipase‑C cascades, intracellular calcium flux, and ERK/MAPK pathway activation — within neuronal and receptor‑expressing model systems. The molecular responses observed vary with receptor subtype, concentration, exposure time, and experimental model, and PT‑141 is used to characterise melanocortin‑receptor signalling rather than to infer defined biological or physiological outcomes.