Abstract: | Piracetam (at concentrations of 10(-6) and 10(-5), but not 10(-4) and 5 X 10(-4) M) decreased K+-stimulated 3H-D-aspartate release. Proline enhanced K+-stimulated D-aspartate release, and its effect was antagonized by piracetam at a concentration that had no effect on K+-stimulated release. Quisqualic acid attenuated K+-stimulated D-aspartate release, with the effect antagonized by GDEE. GDEE also blocked the effect of piracetam, but not proline. The data are discussed in terms of the role of excitatory amino acid neurotransmission in the mechanisms of amnestic and antihypoxic piracetam action. |