The protective effects of Shen Xian Tang on the learning and memory impairment of multiple infarction dementia in rats and its possible mechanism

Objective: It was designed to understand the protective effects of Shen Xian Tang on the Learning and memory impairment of multiple infarction dementia（MID） in rats and its possible mechanisms. Methods: Multiple infarction dementia model in rats were made by injection of liquid paraffin into left ventricular compartment with a dosage of 0.25ml·kg^-1 and Morris water maze was used to detect memory and learning ability of these rats.The contents of superoxide dismutase（SOD）, malondialdehyde（MDA）, and lipofusin（LP） were measureed in rat liver and brain tissues to explore the possible mechanisms of Shen Xian Tang. Results: Large dosage and medium dosage of Shen Xian Tang improved gradually the memory task time and correctness in Morris water maze, it had statistical significance （P＜0.01） on the fifth day of the training of Morris water mazeShen Xian Tang increased the activity of SOD in brain and liver tissues in all 3 dosage group, while it decreased the contents of MDA and LP（P＜0.01） Conclusion: It may conclude that Shen Xian Tang improved the learning and memory abilities in MID rats through the antagonism of free radical injuries in ischemia reperfusion brain