活性氧在七氟醚预处理减轻大鼠海马脑片氧糖缺失损伤中的作用

目的 评价活性氧(ROS)在七氟醚预处理减轻大鼠海马脑片氧糖缺失损伤中的作用.方法 雄性SD大鼠,体重80～100 g,断头处死,剥离海马,符合标准的40片海马脑片随机分为4组(n=10):氧糖缺失组(OGD组)、4%七氟醚预处理组(Sevo组)、ROS清除剂组(MPG组)和4%七氟醚预处理+ROS清除剂组(SM组),采用脑片灌流及电生理技术,细胞外记录海马CAI区缺氧期间和复氧1 h期间的顺向群锋电位(OPS);采用2,3,5-三苯基氯化四氮唑(TYC)染色定量比色法分析脑片损伤程度.结果 与OGD组相比,Sevo组OPS消失时间缩短,OPS恢复程度、OPS恢复率均升高,组织损伤百分率降低(P<0.01);与Sevo组相比,MPG组和SM组OPS消失时间缩短,OPS恢复程度、OPS恢复率降低,组织损伤百分率升高(P

The role of reactive oxygen species in the neuroprotective effect of sevoflurane preconditioning against oxygen-glucose deprivation injury in rat hippocampal slices

Objective To examine whether reactive oxygen species (ROS) is involved in the neuroprotective effect of sevoflurane preconditioning (Sevo-P) against oxygen-glucose deprivation (OGD) injury in rat hippocampal slices.Methods Male SD rats weighing 80-100 g were anesthetized with ether and decapitated. The hippicampi were removed and sngittaUy sliced (400 μm thick) and placed in artificial CSF aerated with 95% O2-5% CO2 Forty hippocampal slices were randomly divided into 4 groups (n=10 each) : group I OGD; group ⅡSevo-P; group ⅢROS scavenger (MPG) and group Ⅳ Sevo-P + MPG. Electrophysiolngical technique was used to record the amplitude of orthodromic population spike (OPS) in the stratum pyramidale of CAI region during OGD and 1 h reoxygenation. TIC staining was used to determine the degree of tissue injury. Results The amplitude of OPS was rapidly abolished during hypoxia and the degree and rate of recovery of OPS were low after 1 h reoxygenation in OGD group (group Ⅰ). In Sevo-P group (group Ⅱ) the time from the start of OGD to complete inhibition of OPS was prolonged and the degree and rate of recovery of OPS were increased as compared with OGD group (group Ⅰ). Pretreatment with MPG alone did not attenuate the effect of OGD on OPS. MPG pretreatment negated the protective effect of sevoflurane pretreatment. The degree of tissue injury was significantly lower in Sevo-P group than in the other groups. Conclusion Sevoflurane preconditioning can attenuate the OGD injury to rat hippocampal slices. The activation of ROS is involved in the protective effect of sevoflurane preconditioning against OGD injury.