Oxytocin

Oxytocin (Cys-Tyr-Ile-Gln-Asn-Cys-Pro-Leu-Gly-NH₂) is a cyclic nonapeptide characterized by an intramolecular disulfide bond linking residues 1 and 6. It functions as a selective agonist at the oxytocin receptor (OXTR), a Gq/11-coupled G protein-coupled receptor that activates phospholipase C signaling, resulting in IP3/DAG generation and intracellular calcium mobilization. Experimental investigations have examined oxytocin’s interactions with neuropeptide signaling networks, receptor-ligand dynamics, intracellular signaling pathways, and molecular communication systems. Its close structural similarity to vasopressin makes it a valuable research tool for comparative receptor selectivity studies, ligand-binding investigations, and mechanistic evaluation of peptide-mediated signaling pathways.