红景天苷并亚低温对全脑缺血再灌注损伤后大鼠脑的保护作用

PROTECTION OF SALIDROSIDE COMBINED WITH MILD HYPOTHERMIA ON RATS WITH TOTAL BRAIN ISCHEMIAREPERFUSION INJURY

目的探讨红景天苷复合亚低温对全脑缺血再灌注损伤后大鼠海马CA1区细胞凋亡及相关蛋白表达的影响及其机制。方法将150只雄性Wistar大鼠随机分为假手术组、模型组、红景天苷组、亚低温组及红景天苷复合亚低温组5组,采用四动脉阻断（4VO）方法建立大鼠全脑缺血再灌注损伤模型,假手术组仅暴露双侧翼孔及游离颈总动脉,不凝闭椎动脉和夹闭颈总动脉。假手术组、模型组、红景天苷组保持肛温36.5℃;亚低温组和红景天苷复合亚低温组大鼠迅速放入4℃环境使肛温降至32.0℃并维持2h。缺血10min后实现再灌注,再灌注24h后,检测神经功能缺失评分（NDS）、海马CA1区细胞凋亡以及海马组织中Bcl-2、bcl-2相关X蛋白质（Bax）的表达情况。结果与模型组相比,红景天苷和亚低温组均能提高神经功能缺损评分、减少细胞凋亡、上调海马组织Bcl-2表达及下调海马组织Bax表达,而且红景天苷复合亚低温组效果更为明显（F=103.14~1 479.17,q=6.32~98.03,P〈0.05）。结论红景天苷和亚低温能够减轻大鼠全脑缺血再灌注损伤程度,且二者复合保护作用更佳,其机制可能与上调Bcl-2、下调Bax表达有关。

Objective To investigate the effects of salidroside combined with mild hypothermia on apoptosis in hippocampal ca1 region of rat with cerebral ischemia/reperfusion（I/R）injury. Methods This study consisted of 150 male Wistar rats,which were evenly randomized to five groups as：sham operation,model,simple salidroside treatment（Sal group）,pure mild hypothermia treatment（Mild group）and salidroside combined with mild hypothermia（Sal＋Mild）.A model of total brain ischemiareperfusion injury in rats was created by four-artery occlusion（4VO）method.The rats in the shame operation group received only exposure bilateral foramen alares and freeing common carotid artery,the vertebral artery and the common carotid artery were not coagulated or occluded.The anal temperatures of rats in the shame operation group,model group and Sal group were maintained at36.5 ℃.The rats in Mild group and Sal＋Mild group were quickly put into the environment of 4℃to reduce the anal temperature to 32.0 ℃and maintained for 2h.Reperfusion was carried out,after 10 min of ischemia,for 24 h,and then neural deficiency score（NDS）,apoptosis in hippoampal ca1 region and the expressions of Bcl-2and bcl-2-related protein（Bax）were detected. Results Compared with the model group,both Sal group and Mild group could raise NDS score,reduce apoptosis,up-regulate the expression of Bcl-2and down-regulate the expression of Bax,the efficacy being more obvious when salidroside combined with mild hypothermia（F=103.14-1 479.17,q=6.32-98.03,P〈0.05）. Conclusion Salidroside and mild hypothermia reduce the extent of total brain ischemia-reperfusion injury,the combination of the two has a better protective effect.Its mechanism is likely to be associated with up-regulation of Bcl-2and down-regulation of Bax.