Experimental Study On The Effect Of Jiannao Yizhi Decoction In Treating Rats With Chronic Cerebral Circulation Insufficiency

Objective:To establish a rat model of chronic cerebral circulation insufficiency,to investigate the functional mechanism and remedy effect of Jiannao Yizhi decoction on learning and memory, hemorheology,oxidative stress and pathological change of CCCI model rats.Methods:50 rats were randomly divided into five groups:sham-operated group,model group, Yangxue Qingnao granule group,high and low dose of Jiannao Yizhi decoction group.We established a CCCI rat model after chronic cerebral hypoperfusion caused by modified permanent bilateral common carotid arteries occlusion(2VO).Each group was lavaged with regulated dose (drugs or saline) for 8 weeks.Morris water maze test and step-down passive avoidance task were adopted to test learning and memory ability of the rats.After that,we detected hemorrheologic indexes by taking blood from abdominal aorta,and then got the brain,separated the cerebral cortex bilateral cerebral cortexs,to measure activity of GSH-PX and content of H₂O₂,separating the left side hippocampus for hematoxylin and eosin staining.Results:1.The Morris water maze test and step-down passive avoidance task manifested:learning and memory ability of the rats in model group decreased significantly compared with sham-operated group(P＜0.01),while the ability increased significantly after treatment in each treated group comPared with model group(P＜0.01 or P＜0.05),moreover,there was no significant difference between 3 treated goups.2.The whole blood viscosity(including low,middle and high shear rate)and the plasma viscosity were significantly higher in CCCI rats compared with sham-operated group(P＜0.01),while the blood viscosity of low and middle shear,the plasma viscosity were reduced in rats of 3 treated groups(P＜0.01 or P＜0.05).Besides,high dose of Jiannao Yizhi decoction had better function of reducing low shear blood viscosity than Yangxue Qingnao granule(P＜0.05).3.Oxidative stress in the brain of model group rats was severe,meaning the GSH-PX activity was decreased in rats of model group(P＜0.01),which was enhanced in rats of treated groups(P＜0.01 or P＜0.05).What's more,the activity of GSH-PX in Yangxue Qingnao granule group approached to sham-operated group(P＞0.05).The content of H₂O₂ in each group didn't reach statistically significance. 4.HE staining manifested:the ischemia injury to neurons of hippocampus in model group was more serious than that in sham-operated group,while the ischemia injury in high dose of Jiannao Yizhi decoction group and Yangxue Qingnao granule group was lighter compared with model group.Conclusion:1.The CCCI rat model established by using modified permanent bilateral common carotid arteries occlusion(2VO) basically simulated a clear cognitive impairment,increased blood viscosity,oxidative stress,and ischemia injury of neurons etc.The rat model simulated well the state of chronic cerebral hypoperfusion of patients with CCCI.2.Jiannao Yizhi decoction improves the learning and memory ability caused by permanent bilateral common carotid arteries occlusion,and has similar effect to Yangxue Qingnao granule.3.Jiannao Yizhi decoction can reduce blood viscosity well.4.Jiannao Yizhi decoction has strong function of anti free radical.5.Jiannao Yizhi decoction has the same function of alleviating ischemia injury significantly as Yangxue Qingnao granule,and the effectiveness is better when high does.