Effect of kynurenic acid on the ischaemia-induced accumulation of glutamate in rat striatum.
We examined the effect of kynurenic acid, a broad spectrum antagonist of excitatory amino acid receptors, on striatal extracellular glutamate and aspartate accumulation induced by a 30 min forebrain ischaemia in rats. Kynurenic acid, given systemically (500 mg kg-1, i.p.) or administered in situ through the dialysis probe (10 mM), markedly depressed the ischaemia-induced increase in glutamate and aspartate concentrations. These results indicate that, during forebrain ischaemia, local glutamate receptors play a major role in glutamate and aspartate accumulation in the striatum. Ischaemia-induced increase in extracellular concentrations of these excitatory amino acids may be due in part to a positive glutamatergic feedback loop via activation of NMDA and/or non-NMDA receptors.
Ghribi
O
O
Laboratoire de Pharmacologie, Faculté des Sciences Pharmaceutiques et Biologiques, Paris, France.
Callebert
J
J
Plotkine
M
M
Boulu
R G
RG
D000818:Animals; D001224:Aspartic Acid / Q000378:metabolism; D003342:Corpus Striatum / Q000187:drug effects* / Q000378:metabolism; D018691:Excitatory Amino Acid Antagonists; D005971:Glutamates / Q000378:metabolism*; D018698:Glutamic Acid; D002546:Ischemic Attack, Transient / Q000378:metabolism*; D007736:Kynurenic Acid / Q000494:pharmacology*; D008297:Male; D017551:Microdialysis; D018377:Neurotransmitter Agents / Q000378:metabolism*; D010477:Perfusion; D016548:Prosencephalon / Q000098:blood supply; D051381:Rats; D017208:Rats, Wistar
D018691:Excitatory Amino Acid Antagonists; D005971:Glutamates; D018377:Neurotransmitter Agents; D001224:Aspartic Acid; D018698:Glutamic Acid; D007736:Kynurenic Acid