三血管阻断与重开放造成的大鼠全脑缺血再灌流损伤的实验研究

AN EXPERIMENTAL STUDY OF CEREBRAL ISCHEMIA- REPERFUSION INJURY INDUCED BY BASILAR ARTERY AND BILATERAL COMMON CAROTID ARTERIES OCCLUSION AND REOPEN

A small hole was chiseled and enlarged to 2f43mm on a side of occipital crest in Wistar rat. Through the window ,the basilar artery was exposed and clipped, the common carotid artery was then clipped bilaterally. After undergoing given ischemic duration,the clippes were released to reperfuse blood into brain in rats. The results indicated that the model of cerebral ischemia-reperfusion injury induced clipping basilar artery and bilateral common carotid arteries and reopening them seqentially was successful. After clipping three vessels,the electroencephalographic activity was suppressed severely during a few seconds,becoming a straight line nearly and maintained on same level throughout ischemic duration of 30. 60 and 90 minutes. Pupillary colour became pale. The histological examination found that the neurons of molecular layer in cerebral cortex and pyramidal cell layer in hippocampus were degenerated slightly,swollen and round,Nissl bodies lessen and interstital edema appeared after 30 minutes of ischemia. Degeneration and edema were exacerbated in 60 minutes after ischemia and became worsen in 90 minutes after ischemia. The reperfusion was performed by removing three clips after various ischemic duration until 60, 120 and 240 minutes for observation. No electroencephalographic recovery was seen in all animals. Pupillary colour became redden. The histological examination showed that neurons degenerated,edema and interstitial edema were more serious in all reperfusion animals than that in various correspondent ischemic duration. With reperfusion duration prolonged,the more lesions exac- erbated. Cerebral coefficient , cerebral water content and cerebral malondialdehyde (MDA) con- cent were increased significantly in 60 minutes after reperfusion as compared with control and is-chemic animals.