Article date: 1988/6/29
PubMed ID: 2899308
Journal name: Neuroscience letters (ISSN: 0304-3940)
6-Cyano-2,3-dihydroxy-7-nitro-quinoxaline (CNQX; FG 9065) is a new excitatory amino acid antagonist. In the spinal cord it has been reported to selectively block responses to acidic amino acids acting at receptors of the non-N-methyl-D-aspartate (non-NMDA) type. Here we report that in rat hippocampal slices bathed in Mg2+-free medium 10 microM CNQX reversibly blocks responses to alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA), quisqualate and kainate but not NMDA. The synaptic response evoked by low frequency stimulation of Schaffer collateral-commissural fibres in 1 mM Mg2+-containing medium is completely blocked by this concentration of CNQX. In contrast the synaptic response evoked in Mg2+-free medium is not fully blocked by CNQX. The CNQX-insensitive component is, however, abolished by addition of a selective NMDA antagonist. The use of CNQX has allowed for the first time selective synaptic activation of NMDA receptors in the hippocampus.
Author List: Blake J F, Brown M W, Collingridge G L
Publication Types: Journal Article; Research Support, Non-U.S. Gov't
Substances mentioned in the article: Oxadiazoles; Quinoxalines; Receptors, N-Methyl-D-Aspartate; Receptors, Neurotransmitter; Ibotenic Acid; alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; Quisqualic Acid; Kainic Acid;
Mesh terms: Animals; Female; Hippocampus/drug effects; Ibotenic Acid/analogs & derivatives; Kainic Acid/physiology; Oxadiazoles/physiology; Quinoxalines/physiology; Quisqualic Acid; Rats; Receptors, N-Methyl-D-Aspartate; Receptors, Neurotransmitter/physiology; Synapses/drug effects; alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid;