A study on CNS effects of milk extract of nuts of Semecarpus anacardium. Linn, (Anacardiaceae)

The main objective of the proposed work is to evaluate the beneficial effect of nuts of S. anacardium, Linn. extracted with milk, on CNS mainly for its locomotor and nootropic activities in different experimental animal models. Dried nuts of S. anacardium were extracted using Siddha method of extraction and the extract subjected for preliminary phytochemical tests. LD₅₀ studies for the extract were conducted up to 2 g/kg dose by following OECD guidelines No. 425. The locomotor activity studied using photoactometer and the nootropics activity was recorded in both interocepitve and exteroceptive models of amnesia. The milk extract of S. anacardium was positively answered for flavonoids, carbohydrates and phenolic compounds. The extract was subjected for LD₅₀ value and even upto 2 g/kg has not produced any lethal effect. No significant alteration in locomotor activity was observed with all the doses (75, 150 and 225 mg/kg) of the extract tested but a slight CNS depressant effect was noted with only 150 mg/kg of the extract. The extract was tested on EPM at different dose levels and all the doses (75, 150 225 and 300mg/kg) have shown an increase in inflexion ratios. But statistically significant results were observed with 150 and 225 mg/kg treated groups only. When tested on Passive avoidance paradigm, a significant increase in SDL values were recorded with 75 and 225 mg/kg treated groups but not with 150 mg/kg treated group. Piracetam had significantly reversed the scopolamine-induced amnesia but the extract failed to show a similar effect. In diazepam and electroshock-induced amnesia models both Piracetam and the extract had reversed the amnesia but effect with the extract was found to be statistically insignificant. The milk extract of nuts of S. anacardium was found to possess nootropic activity.