大鼠中度液压颅脑损伤后氧化应激反应的实验研究

目的：通过建立大鼠中度颅脑液压损伤模型，检测损伤病灶生化指标脂质氧化终产物丙二醛及抗氧化剂谷胱甘肽含量的变化，探讨其与继发性脑损伤之间的关系，为后续研究提供实验基础。方法雄性Sprague-Dawley大鼠48只，随机分成中度颅脑损伤组（mTBI组）和假手术组（sham-TBI组），各24只。以液压中度颅脑损伤指标致伤TBI组。并于伤后6h、24h处死大鼠，通过ELISA技术测定抗氧化剂谷胱甘肽和脂质氧化产物丙二醛在两组的不同表达，采用独立样本t检验评价大鼠颅脑创伤后的氧化应激损伤。结果mTBI组脑组织见损伤灶及蛛网膜下腔出血，HE染色后可见神经元损伤核固缩，细胞坏死呈空泡状，而sham-TBI组未见神经元损伤表现。TBI后mTBI组中丙二醛浓度较sham-TBI组显著升高，随伤后时间延长丙二醛浓度显著升高（t6h＝6.49，P＜0.01；t24h＝11.22，P＜0.01）；而TBI后mTBI组谷胱甘肽浓度显著低于sham-TBI组，随伤后时间延长谷胱甘肽浓度显著降低（t6h＝9.25，P＜0.01；t24h＝11.24，P＜0.01）。结论液压颅脑损伤模型致伤能量能够测量，稳定性及重复性良好，伤情可能分级。中度闭合性颅脑外伤可导致脑组织病理学改变和氧化应激损伤，且氧化应激损伤指标与脑损伤时间有关，外伤后早期阻断氧化应激过程可以起到脑保护作用。

Experimental rodent study on the role of oxidative stress in moderate traumatic brain injury rats

Objective The rat fluid percussion brain injury model was established ,as to investigate the alternate concentration of malondialdehyde and glutathione in the penumbral region of ipsilateral -injured cortex,which were the end product of lipid peroxidation and antioxidant , respectively.The relationship between these two chemicals and secondary brain injury was explored .Methods Totally 48 adult male Sprague-Dawley rats were randomly assigned to 2 groups,moderate-traumatic brain injury（mTBI,n=24）and sham-TBI（n=24）.Moderate TBI was induced to mTBI group ,and sham-TBI rats were induced all surgery procedures without TBI .Malondialdehyde and glutathione levels in the penumbral region of ipsilateral -injured cortex were examined at 6 h and 24 h post-TBI by ELISA to evaluate the oxidative stress injury in the two groups and independent sample t test was used in this evaluation .Results Brain contusion and subarachnoid hemorrhage could be observed in mTBI rats .In brain sections with HE staining , nuclear pyknosis and vesicular neurons could be detected in mTBI rats .However ,no similar injury could be found in mTBI group . The concentration of malondialdehyde in mTBI group was significantly higher than that in sham -TBI group, and the concentration displayed a significant up regulated trend as time went by post -TBI（ t6 h =6.49,P〈0.01;t24 h =11.22 ,P〈0.01 ） .The concentration of glutathione in mTBI group was significantly lower than that in sham-TBI group,and the concentration displayed a significant down-regulated trend as time went by post-TBI（t6 h =9.25,P〈0.01;t24 h =11.24,P〈0.01）.Conclusion The severity of brain injury induced by fluid percussion could be evaluated and classified , and this injury model could be repeated in stable condition .Moderate brain injury results in brain pathological changes and oxidative stress injury .The index of oxidative stress is correlated with injury period .Blockage of the process of the oxidative stress in the early stage post-TBI may play an important rol