title: PGI2 enhanced cAMP content in bovine coronary arteries in the presence of isobutylmethylxanthine.
abstract: Incubation of bovine coronary artery (BCA) rings with isobutylmethylxanthine (IBMX) resulted in a time-dependent increase of cAMP content. This effect was blocked, when the rings were preincubated with indomethacine or 15-hydroperoxy-arachidonic acid for 5 min, indicating that the IBMX-induced increase in cAMP content may depend on endogenous PGI2 formation. PGE2 did not increase the cAMP content in BCA rings. Dipyridamole did not effect cAMP content, when used as a substitute for IBMX. It is suggested that PGI2 stimulates cAMP formation in arterial walls, but that this effect only becomes visible in the presence of a phosphodiesterase inhibitor.
mesh_terms: D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology*; D000818:Animals; D002417:Cattle; D003331:Coronary Vessels / Q000187:drug effects / Q000378:metabolism*; D000242:Cyclic AMP / Q000378:metabolism*; D004176:Dipyridamole / Q000494:pharmacology; D011464:Epoprostenol / Q000494:pharmacology*; D066298:In Vitro Techniques; D007213:Indomethacin / Q000494:pharmacology; D011453:Prostaglandins / Q000494:pharmacology*; D013268:Stimulation, Chemical; D013806:Theophylline / Q000031:analogs & derivatives*; D013997:Time Factors
chemical_list: D011453:Prostaglandins; D004176:Dipyridamole; D013806:Theophylline; D011464:Epoprostenol; D000242:Cyclic AMP; D015056:1-Methyl-3-isobutylxanthine; D007213:Indomethacin