激光多普勒血流仪优化大鼠全脑缺血再灌注模型

Laser Doppler flowmetry optimized the rat model of global cerebral ischemia-reperfusion

目的使用激光多普勒血流仪(LDF)优化大鼠全脑缺血再灌注模型。方法采用夹闭双侧颈总动脉合并低血压的方法建立大鼠全脑缺血再灌注损伤模型。激光多普勒血流仪监测大鼠手术过程中的脑血流变化。水迷宫检测大鼠空间学习记忆能力。HE染色观察大鼠脑组织病理学改变。黄嘌呤氧化酶法,TBA法分别测定大鼠皮层海马中SOD活性改变,MDA含量变化。结果 LDF监测组大鼠全部存活,而无LDF监测组大鼠术后有3只死亡。手术组大鼠在缺血过程中脑血流降低70%,夹闭完成后,血流恢复至缺血前的80%。与假手术组大鼠比较,缺血再灌注大鼠寻台潜伏期、寻台路径显著增加,大脑皮层海马神经元出现严重核固缩、细胞丢失、神经元数目减少,细胞层次紊乱,SOD活性降低,MDA含量显著增加。结论 LDF监测能降低全脑缺血再灌注大鼠死亡率,提高造模成功率;此模型可用于脑缺血再灌注损伤的基础实验研究。

Objective To optimize a rat model of global cerebral ischemia reperfusion by Laser Doppler flowmetry.Methods The global cerebral ischemia reperfusion model was established by bilateral common carotid arteries occlusion with systemic hypotension.The cere- bral blood flow was continuously monitored by moor VMS-LDF laser Doppler blood flow during the operation phase.The Morris water maze was applied to investigate spatial learning and memory function of the rats.Histological examination by HE staining was employed to access the histopathology of cortex and hippocampus neurons.The SOD activity and MDA content in rat cortex and hippocampus were evaluated by xanthinoxidase and TBA method respectively.Results The rats in LDF-monitored I / R group all survived,and there are three rats died in I / R group.The cerebral blood flow was decreased 70% of the baseline during the cerebral ischemia phase and returned to 80% of the baseline at the reperfusion phase.Compared with those of sham group,there were significant increases in the escape latency and swimming trace in is- chemia group.Cortex and hippocampus neurons in model group showed obvious karyopycnosis with remarkable cell loss and irregular cell con- tours.And the SOD activities were reduced and MDA contents were increased in I / R group compared with those of sham group.Conclusions Laser Doppler flowmetry could reduce the mortality and improve the success rate of global cerebral ischemia model; this model could be used to research the basic experimental studies of cerebral ischemia- reperfusion injury.