Article date: 1992/1/1
PubMed ID: 1370080
Journal name: Journal of neurochemistry (ISSN: 0022-3042)
Potassium-induced depolarization of synaptoneurosomes prepared from rat telencephalon was found to increase [3H]amino-3-hydroxy-5-methylisoxazole-4-propionate ([3H]AMPA) binding to the AMPA receptor. The effect required the presence of calcium because it was blocked by the calcium chelator EGTA but was not blocked by an antagonist of the N-methyl-D-aspartate receptor, aminophosphonopentanoate. The depolarization-induced increase in [3H]AMPA binding was markedly reduced by a blocker of voltage-dependent calcium channels, verapamil. Saturation kinetic experiments revealed that the increase in [3H]AMPA binding produced by potassium depolarization was due to an increase in the affinity of the AMPA receptor. These results provide additional support for a critical role of calcium in the regulation of the AMPA receptors. The synaptoneurosome preparation might represent an interesting tool to determine the role of different calcium-dependent enzymes involved in the regulation of the AMPA receptor.
Author List: Bernard J, Massicotte G, Baudry M
Publication Types: Journal Article; Research Support, Non-U.S. Gov't; Research Support, U.S. Gov't, Non-P.H.S.
Substances mentioned in the article: Receptors, AMPA; Receptors, Neurotransmitter; Ibotenic Acid; Egtazic Acid; alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; Verapamil; Potassium; Calcium;
Mesh terms: Animals; Calcium/physiology; Egtazic Acid/pharmacology; Electrophysiology; Ibotenic Acid/analogs & derivatives; Potassium/pharmacology; Rats; Receptors, AMPA; Receptors, Neurotransmitter/metabolism; Synaptosomes/metabolism; Telencephalon/metabolism; Verapamil/pharmacology; alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid;