prostaglandin E2 receptor EP2 subtype, member of the class A family of seven-transmembrane G protein-coupled receptors
Prostaglandin E2 receptor EP2, also called prostanoid EP2 receptor, is one of four receptor subtypes whose endogenous physiological ligand is prostaglandin E2 (PGE2). Each of these subtypes (EP1-EP4) have unique but overlapping tissue distributions that activate different intracellular signaling pathways. Stimulation of the EP2 receptor by PGE2 causes cAMP accumulation through G(s) protein activation, which subsequently produces smooth muscle relaxation and mediates the systemic vasodepressor response to PGE2. Prostanoids are the cyclooxygenase (COX) metabolites of arachidonic acid, which include the prostaglandins (PGD2, PGE2, PGF2alpha), prostacyclin (PGI2), and thromboxane A2 (TxA2). These five major bioactive prostanoids acts as mediators or modulators in a wide range of physiological and pathophysiological processes within the kidney and play important roles in inflammation, platelet aggregation, and vasoconstriction/relaxation, among many others. They act locally by preferentially interacting with G protein-coupled receptors designated DP, EP. FP, IP, and TP, respectively. The phylogenetic tree suggests that the prostanoid receptors can be grouped into two major branches: G(s)-coupled (DP1, EP2, EP4, and IP) and G(i)- (EP3) or G(q)-coupled (EP1, FP, and TP), forming three clusters.
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.