oxytocin receptor, member of the class A family of seven-transmembrane G protein-coupled receptors
Oxytocin is a peptide of nine amino acids synthesized in the hypothalamus and is released from the posterior pituitary gland. Oxytocin plays an important role in sexual reproduction of both sexes and is structurally very similar to vasopressin. Although vasopressin and oxytocin differ only by two amino acids and stimulate the same cAMP/PKA pathway, they have divergent physiological functions. Vasopressin is involved in regulating blood pressure and the balance of water and sodium ions, whereas oxytocin plays an important role in the uterus during childbirth and in lactation.
Comment:based on the structures of some class A family members with bound ligands (peptides or chemicals), agonists, or antagonists
Comment:Small-molecule chemical ligands tend to bind deeper within the receptor core, compared to a peptide ligand neurotensin, which binds towards the extracellular surface of its receptor.
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