Interaction of 1,4-dihydropyridines with somatic Ca currents in hippocampal CA1 neurones of the guinea pig in vitro.
Two distinct Ca currents may be recorded from guinea pig hippocampal CA1 neuronal somata: a non-inactivating (persistent) current and a rapidly inactivating (transient) current. Nimodipine, a 'calcium antagonist', reduced both Ca currents though the transient current was somewhat less sensitive than the persistent current. BAY K 8644, a 'calcium agonist' enhanced the persistent current and shifted the activation threshold for this current to more negative potentials. BAY K 8644 also enhanced the transient Ca current though the effect was very variable. The results demonstrate that Ca channels in hippocampal CA1 neurones possess a dihydropyridine receptor in common with Ca channels in other tissues.
D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester / Q000494:pharmacology*; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D015220:Calcium Channels; D005260:Female; D006168:Guinea Pigs; D006624:Hippocampus / Q000032:analysis / Q000187:drug effects*; D066298:In Vitro Techniques; D007473:Ion Channels / Q000032:analysis / Q000187:drug effects*; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D009431:Neural Conduction / Q000187:drug effects; D009553:Nimodipine / Q000494:pharmacology*; D011978:Receptors, Nicotinic / Q000032:analysis
D015220:Calcium Channels; D007473:Ion Channels; D011978:Receptors, Nicotinic; D009553:Nimodipine; D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester; D002118:Calcium