title: Blockers of NMDA-operated channels decrease glutamate and aspartate extracellular accumulation in striatum during forebrain ischaemia in rats.
abstract: Brain microdialysis was used to study changes in the glutamate and aspartate extracellular concentrations in the striatum of conscious rats submitted to 30 minutes cerebral ischaemia, using the four-vessel occlusion model. Perfusion of the N-methyl-D-aspartate (NMDA) receptor channel blockers, dizocilpine (MK-801; 75 microM) and Mg2+ (2.5 mM), inhibited the ischaemia-induced accumulation of glutamate and aspartate. The AMPA/kainate receptor antagonist, 2,3-dihydroxy-6-nitro-7-sulfamylbenzo (F) quinoxaline (NBQX; 15 microM and 450 microM) had no effect on glutamate and aspartate levels during ischaemia. On the other hand, omission of Ca2+ from the perfusing solution did not alter the increases in glutamate and aspartate induced by ischaemia. These results suggest that the glutamate and aspartate accumulation in four-vessel occlusion ischaemia is mediated by activation of NMDA receptors in a Ca2+ independent manner.
authors.affiliation: Laboratoire de Pharmacologie, Faculté des Sciences Pharmaceutiques et Biologiques, Université René-Descartes, Paris, France.
authors.forename: O
authors.initials: O
authors.lastname: Ghribi
authors.forename: J
authors.initials: J
authors.lastname: Callebert
authors.forename: C
authors.initials: C
authors.lastname: Verrecchia
authors.forename: M
authors.initials: M
authors.lastname: Plotkine
authors.forename: R G
authors.initials: RG
authors.lastname: Boulu
mesh_terms: D000818:Animals; D001224:Aspartic Acid / Q000378:metabolism*; D002545:Brain Ischemia / Q000378:metabolism*; D002118:Calcium / Q000494:pharmacology; D003342:Corpus Striatum / Q000378:metabolism*; D016291:Dizocilpine Maleate / Q000494:pharmacology; D018698:Glutamic Acid / Q000378:metabolism*; D008274:Magnesium / Q000494:pharmacology; D008297:Male; D017551:Microdialysis; D016548:Prosencephalon / Q000098:blood supply / Q000378:metabolism; D011810:Quinoxalines / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D018091:Receptors, AMPA / Q000037:antagonists & inhibitors; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors*
chemical_list: D011810:Quinoxalines; D018091:Receptors, AMPA; D016194:Receptors, N-Methyl-D-Aspartate; C062865:2,3-dioxo-6-nitro-7-sulfamoylbenzo(f)quinoxaline; D001224:Aspartic Acid; D018698:Glutamic Acid; D016291:Dizocilpine Maleate; D008274:Magnesium; D002118:Calcium