The Impact Of Hyperlipidemia On The Expression Of Focal Cerebral Ischemia In Rat Brain Tissue Of Neuronal Nitric Oxide Synthase (nnos)

Objective: In this study, we examine the expression of nNOS after focal cerebral ischemia and reperfusion injury in rats with hyperlipidemia, observe the infarction volume and the morphologic change,investigated the relationship between nNOS and neuronal damage.Methods: The160 wistar rats were randomly divided into two groups: group 1 were fed with mormal forage; group 2 were fed with high-fat forage. After the hyperlipemic rats were made, each group was divided into six group: sham-operated group, simple ischemia 4-hour (4h), ischemia 4h and reperfused 2h,,4h,6h,12h after the middle cerebral artery occlusion (MCAO) . MCAO was established by inserting nylon thread coated with paraffin through the internal carotid artery (ECA) into the anterior cerebral artery (ACA). Then reperfusion was allowed for different time as mentioned above before decapitation. In sham-operated control rats, the thread was only 12 millimeter lone. After the MCAO was made, each of the 6 group was divided into tow groups.group1:Immunocytochemistryt was performed to determine the level of nNOS.group 2 :The infarction volume was observed by 2,3,5-triphenyltetrazolium (TTC) stain. The contents of nitric oxide (NO) in brain were examined with nitric acide reducetase method.Results:(1) MCAO established by inserting nylon thread coated with paraffin is a good ischemia and reperfusion model. (2)Both hyperlipemic rats and not hyperlipemic rats have the maximum infarction volume in the ischemia 4h and reperfused 12h group. In the same infarction and reperfusion time group, the infarction volume of hyperlipemic rats is larger than the normal lipid rats,.(3) Both hyperlipemic rats and normal lipid rats have the maximum expression of nNOS in the ischemia 4h and reperfused 12h group. In the same infarction and reperfusion time group, the expression of nNOS of hyperlipemic rats is more than the normal lipid rats. (4) Contents of NO in cerebrum were increased by the expression of nNOS.Conclusion:(1)The expression of nNOS is upgraded in ischemical reperfusion injury.(2) Hyperlipemia probably aggravate the ischemical reperfusion injury by...