大鼠脑缺血再灌注损伤后不同时间血清SOD和MDA的变化

目的:测定大鼠脑缺血再灌注损伤后不同时间血清超氧化物歧化酶(superoxide dismutase,SOD)活力和丙二醛(malondialdehyde,MDA)含量变化,探讨其随损伤时间的变化规律及在脑损伤发病机制中的作用。方法:建立大鼠脑缺血再灌注损伤动物模型,测定损伤后不同时间大鼠血清中的SOD活力和MDA含量变化,并与假手术对照组进行比较。结果:与假手术组各时点比较,SOD和MDA在再灌注1 h即出现明显变化,随着时间推移与假手术组的差异进一步明显,再灌注36 h达到变化的峰值,随后二者与假手术组的差异呈逐渐减小的趋势,再灌注128 h后差异明显减小,但仍恢复不到假手术组的水平。且二者存在负性相关:SOD活力先降低后升高,MDA含量先升高后降低。结论:SOD和MDA血清学水平变化可以较好地代表脑神经细胞的损伤修复情况,可能一种新的量化指标在临床发展普及,在缺血缺氧性脑损伤疾病的早期发现和治疗评估中发挥作用。

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.