PT-141: Melanocortin Receptor Agonist in Neuroendocrine Research

PT-141 (Bremelanotide) is a synthetic cyclic heptapeptide studied in preclinical neuroendocrine research for its role in melanocortin receptor binding and hypothalamic signaling pathway analysis.

PT-141 (Bremelanotide) is a synthetic cyclic heptapeptide analogue of alpha-melanocyte-stimulating hormone (alpha-MSH), structurally derived from Melanotan II through selective removal of its C-terminal amino acid residues. CAS: 189691-06-3. Unlike linear peptide fragments, PT-141 retains a cyclic backbone believed to confer greater resistance to enzymatic degradation, which has made it a frequently referenced tool compound in preclinical melanocortin receptor research.

The Melanocortin Receptor System

Melanocortin receptors (MC1R through MC5R) are a family of G protein-coupled receptors distributed across a range of tissue types, from skin melanocytes to hypothalamic neurons and adrenal cortex cells. Each subtype is associated with distinct physiological research domains: MC1R with pigmentation biology, MC2R with adrenocortical signaling, and MC3R/MC4R with central nervous system pathways in the hypothalamus. PT-141 is studied as a non-selective agonist across several of these subtypes, making it a useful pharmacological probe for comparative receptor research.

MC3R and MC4R Binding Mechanism Research

Research interest in PT-141 centers substantially on its binding affinity at MC3R and MC4R, two subtypes expressed at high density within hypothalamic nuclei. Studies examining receptor-ligand interaction have used PT-141 to characterize activation kinetics, receptor internalization, and downstream G protein coupling at these sites. Because MC3R and MC4R are implicated in a range of central signaling pathways, PT-141 continues to serve as a reference agonist in structure-activity relationship studies of the melanocortin receptor family.

Hypothalamic Signaling Pathway Analysis

  • Used to probe cAMP/PKA second-messenger cascade activation following melanocortin receptor binding in hypothalamic cell models
  • Studied for receptor internalization and desensitization kinetics at MC3R and MC4R in vitro
  • Investigated as a comparative ligand alongside alpha-MSH in receptor selectivity assays
  • Referenced in research examining melanocortin signaling crosstalk with other hypothalamic neuropeptide systems
  • Used in structure-activity relationship studies to map the cyclic peptide backbone's contribution to receptor affinity

For in-vitro research use only. Not for human or veterinary use.