Article date: 1991/12/24
PubMed ID: 1687672
Journal name: Brain research (ISSN: 0006-8993)
Activation of metabotropic glutamate receptors (mGluRs, QP or ACPD receptors) has recently been shown to cause depolarization, blockade of the slow after-hyperpolarization and depression of calcium currents in hippocampal pyramidal cells. Here, we report evidence for a new mGluR-mediated effect: slowing of the spike repolarization in CA1 cells in rat hippocampal slices. During blockade of the ionotropic glutamate receptors, the mGluR agonists trans-1-amino-cyclopentyl-1,3-dicarboxylate (t-ACPD), quisqualate or L-glutamate caused spike broadening. In contrast, the ionotropic receptor agonist alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionate (AMPA) was ineffective. The spike broadening may act in concert with the other mGluR effects, e.g. by further increasing the influx of Ca2+ ions which, in turn, may contribute to synaptic modulation.
Author List: Hu G Y, Storm J F
Publication Types: Journal Article; Research Support, Non-U.S. Gov't
Substances mentioned in the article: Glutamates; Phorbol Esters; Receptors, Glutamate; Receptors, Neurotransmitter; Cycloleucine; phorbol-12,13-diacetate; Ibotenic Acid; cispentacin; Glutamic Acid; alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; Quisqualic Acid;
Mesh terms: Action Potentials/drug effects; Animals; Cycloleucine/analogs & derivatives; Female; Glutamates/metabolism; Glutamic Acid; Hippocampus/physiology; Ibotenic Acid/analogs & derivatives; In Vitro Techniques; Kinetics; Male; Neurons/drug effects; Phorbol Esters/pharmacology; Pyramidal Tracts/physiology; Quisqualic Acid/pharmacology; Rats; Rats, Inbred Strains; Receptors, Glutamate; Receptors, Neurotransmitter/drug effects; alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid;