局部亚低温联合硫酸镁对局灶性脑缺血大鼠的保护作用

目的:探讨联合应用局部亚低温(32-35℃)及硫酸镁对局灶性脑缺血大鼠的保护作用及其可能机制。方法:通过线栓法建立大鼠大脑中动脉阻塞(MCAO)模型,将40只雄性Wistar大鼠随机分为假手术组、常温组、亚低温组、硫酸镁组、亚低温+硫酸镁组,每组8例,采用Longa神经功能评分、TTC染色、TUNEL技术,检测和比较各组脑缺血后大鼠的神经功能、脑梗死体积、凋亡细胞数。结果:与常温组相比,亚低温组与亚低温+硫酸镁组的梗死体积、神经功能评分、凋亡细胞数均明显降低,差异有显著意义(P0.05);而与亚低温组相比,亚低温+硫酸镁组局灶脑缺血大鼠的脑梗死体积、神经功能评分、凋亡细胞数均显著减少,差异有显著意义(P0.05)。结论:与单独应用亚低温相比,局部亚低温与硫酸镁联合应用,对局灶性脑缺血大鼠可发挥更有效的脑保护作用,其机制可能与抑制脑缺血后凋亡有关。

Protective Effect of Focal Mild Hypothermia Combined with MgSO4 on theRats with Focal Cerebral Ischemia

Objective:To investigate the protective effect of focal mild hypothermia combined with MgSO4 on the rats with focalcerebral ischemia and its possible mechanism.Methods:The middle cerebral artery occlusion(MCAO) models of rat were achieved by anintraluminal filament. Forty male adult Wistar rats were randomly divided into sham-operated group, normothermia ischemia group,MgSO4 group, mild hypothermia group and mild hypothermia+ MgSO4 group (each group n=8). The neurological function, infarctvolumes, apoptotic cell numbers in the ischemic cortex were assessed by Longa neurological scores, TTC staining and TUNEL.Results:Compared with the normothermia group, the neurological scores, infarct volumes and apoptotic cell numbers markedly decreased inhypothermia group and hypothermia+MgSO4 group (P<0.05). Compared with mild hypothermia group, the neurological scores, infarctvolumes and apoptotic cell numbers markedly decreased in hypothermia+MgSO4 group (P<0.05).Conclusion:Focal mild hypothermiacombined with MgSO4 was more effective in the protection of rats with focal cerebral ischemia than mild hypothermia, which was partlydue to the decrease of apoptosis.