title: Mouse prostaglandin E receptor EP3 subtype mediates calcium signals via Gi in cDNA-transfected Chinese hamster ovary cells.
abstract: We recently cloned the mouse prostaglandin (PG) E receptor EP3 subtype that is coupled to adenylate cyclase inhibition through Gi and identified three isoforms which are produced through alternative splicing. In Chinese hamster ovary cells expressing each EP3 isoform, PGE2 induced an immediate increase in the intracellular Ca2+ concentration ([Ca2+]i) due to both Ca2+ mobilization from internal stores and influx from the extracellular medium. This increase was abolished by prior treatment with pertussis toxin (PT). PGE2 also stimulated an accumulation of inositol trisphosphate (IP3) in a PT-sensitive manner. Both the PGE2-induced increase in [Ca2+]i and accumulation of IP3 were blocked by the phospholipase C inhibitor U-73122. Thus, EP3 is linked to phospholipase C activation via Gi, and this activation leads to Ca2+ mobilization from internal stores and influx from the extracellular medium.
authors.affiliation: Department of Physiological Chemistry, Faculty of Pharmaceutical Sciences, Kyoto University, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Irie
authors.forename: E
authors.initials: E
authors.lastname: Segi
authors.forename: Y
authors.initials: Y
authors.lastname: Sugimoto
authors.forename: A
authors.initials: A
authors.lastname: Ichikawa
authors.forename: M
authors.initials: M
authors.lastname: Negishi
mesh_terms: D037361:Adenylate Cyclase Toxin; D000262:Adenylyl Cyclases / Q000378:metabolism; D000818:Animals; D016466:CHO Cells; D002118:Calcium / Q000378:metabolism*; D003001:Cloning, Molecular; D006224:Cricetinae; D018076:DNA, Complementary / Q000378:metabolism; D015232:Dinoprostone / Q000494:pharmacology*; D019204:GTP-Binding Proteins / Q000378:metabolism*; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism; D007700:Kinetics; D051379:Mice; D037342:Pertussis Toxin; D018078:Receptors, Prostaglandin E / Q000096:biosynthesis / Q000502:physiology*; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000378:metabolism; D015398:Signal Transduction / Q000187:drug effects; D014162:Transfection; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
chemical_list: D037361:Adenylate Cyclase Toxin; D018076:DNA, Complementary; D018078:Receptors, Prostaglandin E; D011994:Recombinant Proteins; D010566:Virulence Factors, Bordetella; D015544:Inositol 1,4,5-Trisphosphate; D037342:Pertussis Toxin; D019204:GTP-Binding Proteins; D000262:Adenylyl Cyclases; D015232:Dinoprostone; D002118:Calcium