SCH 58261 differentially influences quinolinic acid-induced effects in striatal and in hippocampal slices.

The influence of the adenosine A(2A) receptor antagonist SCH 58261 (7-(2-phenylethyl)-5-amino-2-(2-furyl)-pyrazolo-[4,3-e]-1,2,4-trizolo[1,5-c] pyrimidine) (50, 200 nM, 1 microM) on quinolinic acid effects has been studied in rat striatal and hippocampal slices. Quinolinic acid induced disappearance of field potentials at concentrations of 500 microM and 2 mM in hippocampal and corticostriatal slices, respectively. We found that 1 microM SCH 58261 prevented quinolinic acid-induced field potential disappearance in corticostriatal but not in hippocampal slices. This finding demonstrates that the peculiar binding profile of SCH 58261 and the predominance in the hippocampus of "atypical" adenosine A(2A) receptor population (not recognized by SCH 58261) could have a functional relevance in the occurrence of region-specific neuroprotective effects.