Effect of arachidonic acid on [3H]D-aspartate outflow in the rat hippocampus.
The aim of this study was to investigate the effect of arachidonic acid on [3H]d-aspartate outflow in rat hippocampus synaptosomes and slices. Arachidonic acid 1) increased basal outflow of [3H]d-aspartate in both synaptosomes and slices, and 2) increased K(+)-evoked overflow in slices but not in synaptosomes. The latter effect was dependent (at least in part) on arachidonic acid metabolism, most likely mediated by lipo-oxygenase metabolites and free radical production. It was prevented by nordihydroguairetic acid but not by indomethacin, and was significantly reduced by free radical scavengers (superoxide-dismutase and catalase). This effect was dependent upon stimulation since it could not be observed after a continuous perfusion of arachidonic acid in the absence of stimulation. Furthermore, it was long-lasting since a 30 min perfusion of arachidonic acid was sufficient to exert a significant effect on a stimulation following termination of the application.
Simonato
M
M
Institute of Pharmacology, University of Ferrara, Italy.
Bregola
G
G
Bianchi
C
C
Beani
L
L
D000818:Animals; D016718:Arachidonic Acid / Q000494:pharmacology*; D001224:Aspartic Acid / Q000378:metabolism*; D001481:Basal Metabolism; D015415:Biomarkers / Q000737:chemistry; D005609:Free Radicals; D005971:Glutamates / Q000378:metabolism*; D006624:Hippocampus / Q000187:drug effects* / Q000378:metabolism; D066298:In Vitro Techniques; D008084:Lipoxygenase / Q000378:metabolism; D008297:Male; D011188:Potassium / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013574:Synaptosomes / Q000187:drug effects / Q000378:metabolism; D014316:Tritium
D015415:Biomarkers; D005609:Free Radicals; D005971:Glutamates; D014316:Tritium; D016718:Arachidonic Acid; D001224:Aspartic Acid; D008084:Lipoxygenase; D011188:Potassium