Oxiracetam prevents electroshock-induced decrease in brain acetylcholine and amnesia

Abstract

In the rat, 1 min following electroshock (ECS) a 46 and 39% decrease in acetylcholine levels was found in the hippocampus and cerebral cortex, respectively. The decrease in the hippocampus was still statistically significant 30 min after ECS. The ECS applied 1 min after training also disrupted the performance of a passive avoidance conditioned response ('step down') tested 30 min later. Oxiracetam (100 and 300 mg/kg i.p.) administered 90 min before training prevented, in a dose-dependent manner, the decrease of acetylcholine in the cerebral cortex and hippocampus. Oxiracetam prevented the ECS disruption of the acquisition of a passive avoidance response. At the dose of 300 mg/kg the acetylcholine level 1 min after ECS was significantly higher than in the sham-treated rats. Piracetam at the same doses was inactive. These results support the hypothesis that oxiracetam may prevent the disruption of the conditioned response by acting on cortical and hippocampal cholinergic mechanisms.