The effect of paeoniflorln on rat model of vascular dementia acetylcholinesterase and superoxide dismutase

Objective To observe the effect of paeoniflorin(PF) on the vascular dementia rats learning and memory ability,and acetylcholinesterase(AchE),superoxide dismutase(SOD) level.Methods Fifty Wistar rats were randomly divided into sham operation group,model group,drug group(paeoniflorin low dose group with 12.5 mg/kg,middle dose group with 25 mg/kg,high dose group with 50 mg/kg),with 10 rats in each group.The model group and the treatment group by repeated clamping of bilateral common carotid artery(CCA) model combined with intraperitoneal injection of sodium nitroprusside,sham operation group did not block the CCA and injection of sodium nitroprusside.After second day of establish the mode,treatment group was given intragastric administration,the model group and the sham operation group were given normal saline,1 times a day,continuous 30 d.Application of Morris water maze test,step-down test the learning and memory ability of rats,and comparison of AchE,SOD activity.Results(1) Morris water maze experiment:model group and sham operation group positioning navigation test in escape latency gradually shortened,fifth days shorter than first days(P 0.05);compared with the sham operation group,model group were prolonged incubation at each time point,and through the platform was significantly reduced(P 0.01);compared with the model group,drug group latency showed a trend of shortening,fifth days more shorter than first days(P 0.05);times across the platform significantly increased(P 0.05 or P 0.01).(2) In step-down test:compared with the sham operation group,model group,the number of errors increased significantly,and was significantly shortened(P 0.01);compared with the model group,the 3 groups were significandy decreased the number of errors,the latency was higher than that in the model group(P 0.05 orP 0.01).Compared with the low,middle dose group,high dose group had significantly more prolonged latency(P0.01).(3) AchE,SOD activity of brain homogenates;compared with the sham operation group,model group,AchE decreased,SOD activity increased(P 0.01);compared with the model group,low,middle and high dose groups AchE activity decreased,SOD activity increased(P 0.05 orP 0.01);compared with the low dose group,high dose group AchE activity decreased(P 0.05),the activity of SOD increased significandy(P 0.01);compared with middle dose group,high dose group s activity of SOD increased(P 0.05).Conclusion Paeoniflorin improved vascular dementia rats learning and memory ability,one of the possible mechanisms is on the basis of inhibition of AchE activity to increase the activity of SOD.