Study on Acute Toxicity and Learning-memory Improvement of Schisandra Chinensis and Polygalatenuifolia Extracts

Objective To elucidate the effective chemical components of Schisandra chinensis and Polygalatenuifolia on improving learning and memory. Methods We prepared the ethanol extracts of Schisandra chinensis and Polygalatenuifolia and tested for their maximal tolerance dose(MTD) and 50% lethal dose(LD_(50)).Furthermore,we tested the number of correct response and the trails in mice that have been administered with Schisandra chinensis and Polygalatenuifolia ethanol extracts by using the radial-arm maze respectively. Results MTD of Schisandra chinensis was 58.88g/kg,which was as 490 times than the maximal dose used in humans.LD_(50) of Polygalatenuifolia was 14.26g/kg.All mice which have been administered with Schisandra chinensis and Polygalatenuifolia ethanol extracts improved significantly the number of correct response and diminished the trails(P0.05 or P0.01). Conclusions These results suggest that toxicity of Schisandra chinensis and Polygalatenuifolia ethanol extracts are low and could think to be innocuous,and the effective components of Schisandra chinensis and Polygalatenuifolia on improving learning and memory might be concentrated in their ethanol extracts.