ABSTRACT
Objective To investigate the expression of adiponectin (APN) and the clinical significance in type 2 diabetic rats with cerebral ischemic reperfusion damage.Methods One hundred and four SD rats were randomly divided into two groups,including normal diet group (n=52) and diabetic diet group (n=52); middle cerebral artery occlusion was performed in some of the rats to induce ischemia reperfusion injury models.Normal diet group was then randomly divided into euglycemia group (n=8) and ischemia reperfusion group (I/R,n-44); diabetic diet group was randomly divided into diabetes groups (n=8) and diabetes complicated with ischemia reperfusion group (DM+I/R,n=44).The blood was collected to detect the APN changes from the tail vein of rats from diabetes group (n=4) and DM+I/R group (n=4) before MCAO surgery and at 3,6,24,48 and 72 h,and 7 d after reperfusion.The rest 40 rats were randomly divided into subgroups subjected to 90 min of focal ischemia followed by 3,6,24 and 72 h,and 7 d reperfusion (n=8); the neuroethology assessment was determined by Zea Longa method; morphology of brain tissue was observed by HE staining.APN expression in infarction cores was detected by immunohistochemistry and Western blotting.Results The assessment scores of DM+I/R group (2.79±0.41) were significantly higher than those of I/R group (1.27±0.45,P＜0.05).As compared with that in the I/R group,the serum APN level in the DM+I/R group was significantly decreased 3,6,24,48 and 72 h,and 7 d after reperfusion (P＜0.05).Cerebral tissue damage (cellular degeneration and necrosis) in DM+I/R group was more serious as compared with I/R group at the same reperfusion time.In the ischemic hemisphere,APN expression increased at 3 h,decreased at 6 h,and increased again till 24 h after reperfusion,and then it remained at high level up to 7 days after reperfusion.The expression of APN in DM+I/R group was significantly lower than that in the I/R group (P＜0.05).These findings were consistent with the results of Western blotting.Conclusion APN expression decreases after focal cerebral ischemia-reperfusion injury,indicating that APN plays an important role in aggravating ischemic reperfusion injury by diabetes.