PT-141 (Bremelanotide)

PT-141 is a cyclic melanocortin agonist selective for MC3R/MC4R with minimal MC1R activity. The first melanocortin peptide identified to act through CNS mechanisms for sexual function and autonomic signaling research.

PT-141 (Bremelanotide, chemical name: Ac-Nle-c[Asp-His-D-Phe-Arg-Trp-Lys]-OH) is a cyclic heptapeptide melanocortin receptor agonist structurally derived from Melanotan 2 (MT-2). The key structural difference is the C-terminal free acid (-OH) in PT-141 versus the C-terminal amide (-NH₂) in MT-2, resulting from a metabolic conversion first observed during MT-2 research. This seemingly minor modification significantly shifts the receptor selectivity profile: PT-141 demonstrates preferential agonist activity at MC3R and MC4R with substantially reduced affinity for MC1R compared to MT-2, resulting in minimal melanogenic (pigmentation) activity at research-relevant concentrations.

The primary research interest in PT-141 centers on MC4R-mediated central nervous system signaling. MC4R is expressed in hypothalamic nuclei, particularly the paraventricular nucleus (PVN), where its activation initiates descending signaling pathways through the brainstem (ventrolateral medulla) and spinal cord (sacral parasympathetic nucleus) that modulate autonomic outflow to pelvic organs. Published research has demonstrated that MC4R activation by PT-141 triggers downstream dopaminergic signaling and nitric oxide production in target tissues. This CNS-mediated mechanism distinguishes PT-141 from PDE5 inhibitors, which act peripherally on vascular smooth muscle — making it a valuable research tool for studying central versus peripheral autonomic regulatory pathways.

Additional research applications include melanocortin receptor pharmacology (MC3R/MC4R selective agonist studies), hypothalamic autonomic control circuitry mapping, dopamine-melanocortin signaling cross-talk, and appetite/energy homeostasis research (MC4R plays a well-documented role in energy balance, with loss-of-function MC4R mutations being the most common monogenic obesity gene in humans).

Supplied as a lyophilized powder with ≥99% purity. Store at -20°C desiccated. For neuropharmacology and melanocortin receptor research only.

Product Specifications

Certificate of Analysis

Every batch ships with a Janoshik-verified COA covering HPLC purity, mass spectrometry confirmation, and batch traceability.

Shipping & Lead Times

• US warehouse: ships within 1–2 business days · estimated 3–5 day delivery
• HK warehouse: ships within 2–3 business days · estimated 7–14 day international delivery
• Carriers: DHL Express, FedEx International, UPS Worldwide
• Discreet outer packaging — no peptide branding visible
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