The Research On The Plasma Homocysteine Of Cerebral Ischemia Reperfusion Synthetic Vascular Dementia Rat

Objective: We adopted the repeated occlusion of bilateral common carotid arteries and abdominal injection of sodium nitroprusside in SD rats to produce the repeated forebrain ischemia-reperfusion injure, which produced the models of simulating vascular dementia. and mensurated the plasma homocysteine levels.To observe the relationship between the plasma homocysteine levels and vascular dementia.Methods:A total of 45 healthy male SD rats were divided randomly into normal control group (n=10),sham-operated control group(n=10) and model group (n=25). We duplilicated the model of vascular dementia rat with the repeatedly occlusion of bilateral common carotid artery and an abdominal injection of sodium nitroprusside on the model groups. On the sham-operated control group,the operation process is same to the model group, but with no repeatedly occlusion of bilateral common carotid artery and reducing blood pressure with an abdominal injection of sodium nitroprusside. The normal control group weren't do the operation processing. 7 days late,The behavior ability of learning,memory and intelligence were observed by using Morris water maze ,and the microcosmic changes of neurons in hippocampus CA1 area were detected by HE staining and Nissl staining in different groups. The plasma Hcy levels were assayed by high-performance liquid chromatography (HPLC).Results:1. The Morris water maze showed that the repeated forebrain ischemia-reperfusion injure leaded to learning and memory impairment of the rats. The rats in the model groups presented a significant difference with control group and sham-operated group (P<0.01). However, there was no significant difference between the group of sham-operated and normal control (P>0.05). The dementia rate of rats was 84%.2. The modality change showed that the pyramidal cell of hippocampus in CA1 region appeared ischemic changes, such as pyknosis, denaturation, necrosis and degeneration. The cell count in the model groups presented a significant difference with control group and sham-operated group (P<0.01). However, there was no significant difference between the group of sham-operated and normal control (P>0.05).3. The plasma homocysteine levels in the model group were significantly higher than those in the sham-operated group and normal control (P<0.05). However, there was no significant difference between the group of sham-operated and normal control (P>0.05).Conclusion:1. This model of vascular dementia is useful for studying vascular dementia. It has the practicability and can be used in basic experiment studying.2. The plasma homocysteine levels a correlation with vascular dementia, may be a guide line of diagnoses for the vascular dementia.