Changes of serum SOD and MDA level of middle cerebra lartery occlusion models in Sprague Damley rats

Objective:To investigate the dynamic changes of superoxide dismutase（SOD） and malondialdehyde（MDA） in serum of rats during experimental traumatic brain injuries and to explore the role of SOD and MDA in the mechanism of pathologic injuries.Methods:Sprague Damley male rats were subjected to 90 min of focal ischemia induced by middle cerebral artery occlusion（MCAO） with a filament insert,followed by 1 h,4 h,8 h,16 h,32 h,64 and 128 h of reperfusion.Sham operated rats not subjected to MCAO served as controls.The serum was taken after reperfusion in the all groups,respectively,for determination of SOD activities by xanthine oxidase method and MDA content by thibabituric acid method.Results:The activity of SOD decreased immediately after operation,came to the lowest point after 36h,then increased in the following time,whereas the leaves of MDA came to the highest point after 36 h,then decreased.They had negative correlation.Conclusion:Serum levels of SOD and MDA may be popularly used as a new index on early diagnosis and treatment assessment in hypoxic-ischemic encephalopathy.