title: Enhancement of long-term potentiation by the calcium channel agonist Bayer K8644 in CA1 of the rat hippocampus in vitro.
abstract: The effect of the Ca agonist BAY K8644 was studied on long-term potentiation (LTP) of extracellular excitatory postsynaptic potentials in the stratum radiatum of CA1 of the hippocampus in vitro. LTP was evoked by brief trains of high-frequency stimulation applied to the stratum radiatum of CA1. 0.5% Ethanol, the vehicle used to dissolve BAY K8644, reduced LTP from 43% to 15%. An amount of 15 microM BAY K8644, in 0.5% ethanol, enhanced LTP from 13% in the ethanol control to 57%. The Ca channel antagonist verapamil did not alter control LTP, but did inhibit the potentiating action of BAY K8644 on LTP. It is postulated that the enhancement of LTP by BAY K8644 may occur through enhancement of Ca influx through voltage-dependent Ca channels.
mesh_terms: D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester / Q000494:pharmacology*; D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D002118:Calcium / Q000502:physiology*; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D004558:Electric Stimulation; D000431:Ethanol / Q000494:pharmacology; D006624:Hippocampus / Q000187:drug effects / Q000502:physiology*; D066298:In Vitro Techniques; D051381:Rats; D011919:Rats, Inbred Strains; D011930:Reaction Time / Q000187:drug effects
chemical_list: D002121:Calcium Channel Blockers; D000431:Ethanol; D001498:3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethyl-5-nitro-4-(2-(trifluoromethyl)phenyl)-, Methyl ester; D002118:Calcium