Stimulation of calcium uptake in PC12 cells by the dihydropyridine agonist BAY K 8644.
Methyl 1,4-dihydro-2, 6-dimethyl-3-nitro-4-(2-trifluoromethylphenyl)-pyridine-5-carboxylate (BAY K 8644), an analog of dihydropyridine calcium channel antagonists, stimulated 45Ca uptake into PC12 pheochromocytoma cells. Half-maximal stimulation occurred at 80 nM BAY K 8644. Enhancement of uptake was inhibited by cationic and organic calcium channel blockers, but not by tetrodotoxin, which is consistent with an effect on voltage-dependent calcium channels. Stimulation of 45Ca uptake by BAY K 8644 occurred only at elevated concentrations of extracellular K+, suggesting that BAY K 8644 may interact with calcium channels in the open (activated) state.
D A
DA
Greenberg
C L
CL
Carpenter
E C
EC
Cooper
D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester; D000310:Adrenal Gland Neoplasms / Q000378:metabolism; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002460:Cell Line; D004095:Dihydropyridines; D004305:Dose-Response Relationship, Drug; D009543:Nifedipine / Q000031:analogs & derivatives* / Q000494:pharmacology; D009568:Nitrendipine; D010673:Pheochromocytoma / Q000378:metabolism; D011725:Pyridines / Q000037:antagonists & inhibitors*; D051381:Rats
D004095:Dihydropyridines; D011725:Pyridines; D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester; C038806:1,4-dihydropyridine; D009568:Nitrendipine; D009543:Nifedipine; D002118:Calcium