Evaluation of nootropic and neuroprotective effects of low dose aspirin in rats

Objective: To evaluate the nootropic and neuroprotective effects of aspirin in Sprague Dawley rats. Materials and Methods: Retention of conditioned avoidance response (CAR) and central 5-HT-mediated behavior (lithium-induced head twitches) were assessed using repeated electroconvulsive shock (ECS) in rats. Rats were divided into eight groups: control (pretreated with distilled water), scopolamine (0.5 mg/kg i.p.), ECS (150 V, 50 Hz sinusoidal with intensity of 210 mA for 0.5 s) pretreated, aspirin (6.75 mg/kg orally) pretreated, combined scopolamine and aspirin pretreated, ondansetron (0.36 mg/kg orally) pretreated, combined ECS and ondansetron pretreated and combined ECS and aspirin pretreated groups. Data was analyzed by the chi-square test and ANOVA. Results: Findings show that administration of single ECS daily for consecutive 8 days results in enhancement of 5-HT-mediated behavior (lithium-induced head twitches) and in disruption of the retention of CAR. Aspirin and ondansetron administration significantly increased the retention of conditioned avoidance response compared to control. Ondansetron and aspirin significantly prevented ECS-induced attenuation of the retention of conditioned avoidance response also. On the other hand, ondansetron and aspirin significantly retarded the ECS-induced enhancement of 5-HT-mediated behavior. Conclusion: Inhibition of the serotonergic transmission by aspirin is responsible for its nootropic and neuroprotective actions.