实验性颅脑伤大鼠脑组织SOD和MDA的变化

Changes of superoxide dismutase and malondialdehyde in cerebral tissues of rats during experimental traumatic brain injury

目的:观察实验性颅脑伤大鼠脑组织超氧化物歧化酶(SOD)和丙二醛(MDA)的动态变化,探讨SOD和MDA在颅脑伤病理损伤机制中的作用。方法:采用自由落体致伤方法制备大鼠颅脑伤模型(模型组),并以正常大鼠作对照(对照组),分别于造模后3、5和7d处死动物取脑,测定海马和皮质中SOD活力和MDA含量。结果:模型组大鼠海马SOD活力在3个时间点均显著低于对照组.而MDA含量均显著高于对照组;模型组大鼠皮质SOD活力在造模后3、5d时显著低于对照组,而MDA含量则显著高于对照组,到7d时二者与对照组均无明显差异。结论:大鼠颅脑伤时脑组织SOD活力显著降低,而MDA含量则显著增高,提示SOD和MDA可能参与颅脑伤病理损伤机制并在其中发挥重要作用。

Objective: To observe the dynamic changes of superoxide dismutase (SOD) and malondialde-hyde (MDA) in cerebral tissues of rats during experimental traumatic brain injuries and to explore the role of SOD and MDA in the mechanism of pathologic injuries. Methods:The models of traumatic brain injury were made with free-falling objects (the model group). Healthy rats were taken as control (the control group). The rats were executed for cerebral tissues at 3, 5 and 7 days after the models were made,and the activities of SOD and the levels of MDA in hippocampus and cerebral cortex were determined. Results:The activities of SOD in hippocampus of rats in the model group were significantly lower than that in the control group at all the three time points, whereas the levels of MDA were significantly higher than that of the control group. The activities of SOD in cerebral cortex were significantly lower than that of the control group at 3 and 5 days after the models were made, whereas the levels of MDA were significantly higher than that of the control group. There was no significant difference between the two groups at 7 days after the models were made. Conclusion: The activities of SOD in cerebral tissues of rats reduced significantly during the traumatic brain injury, but the levels of MDA increased significantly. This suggests that SOD and MDA may participate in the pathologic damaging mechanism of traumatic brain injury and play an important role in it.