title: Some effects of the calcium promotor BAY K 8644 on feline cerebral arteries.
abstract: The proposed calcium promotor BAY K 86(44) contracted feline basilar arteries partially depolarized by 10 mmol X 1(-1) potassium in a concentration-dependent manner (EC50 value: (2.1 +/- 1.2) X 10(-9) mol X 1(-1)). The concentration-response curve for prostaglandin (PG) F2 alpha was displaced to the left after pretreatment with BAY K 86(44). PGF2 alpha induced a biphasic contraction in calcium-free medium as has been described previously. The second PGF2 alpha-induced contraction phase in calcium-free medium was abolished by pretreatment with nifedipine or diltiazem. BAY K 86(44) restored the second phase in arteries pretreated with nifedipine, but not in vessels pretreated with diltiazem. The findings suggest that BAY K 86(44) acts as a promotor of calcium-influx, probably by interaction with the 'dihydropyridine receptor' in the cell membrane, and also provide support for the view that PGF2 alpha releases membrane-bound calcium.
authors.forename: T K
authors.initials: TK
authors.lastname: Uski
authors.forename: K E
authors.initials: KE
authors.lastname: Andersson
mesh_terms: D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester; D000818:Animals; D001488:Basilar Artery / Q000187:drug effects; D002118:Calcium / Q000378:metabolism* / Q000494:pharmacology; D002415:Cats; D002536:Cerebral Arteries / Q000187:drug effects*; D015237:Dinoprost; D066298:In Vitro Techniques; D007473:Ion Channels / Q000187:drug effects*; D009543:Nifedipine / Q000031:analogs & derivatives* / Q000494:pharmacology; D011460:Prostaglandins F / Q000494:pharmacology; D014661:Vasoconstriction / Q000187:drug effects
chemical_list: D007473:Ion Channels; D011460:Prostaglandins F; D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester; D015237:Dinoprost; D009543:Nifedipine; D002118:Calcium