深低温停循环不同时间点犬脑皮质半胱氨酸天门冬氨酸蛋白酶-3mRNA的表达

目的利用实时荧光定量聚合酶链反应(PCR)分析半胱氨酸天门冬氨酸蛋白酶-3 mRNA(Caspase-3 mR-NA)在深低温停循环(DHCA)过程中的表达,探讨DHCA对神经细胞凋亡的影响,为深低温停循环后脑损害的研究和防治提供资料。方法选择健康成年杂种犬10只,建立DHCA模型,分别于体外循环0 min、停循环0 min、停循环30 min、停循环60 min、复温再灌注45 min取脑皮质迅速冻存,待全部动物实验结束后统一行实时荧光PCR定量检测Caspase-3mRNA的表达情况。结果体外循环后特别是降温后Caspase-3 mRNA的拷贝数先下降,DHCA 0 min达最低值,随着DHCA过程的延长,Caspase-3 mRNA的表达逐渐增强,复温再灌注45 min达最大值,不同时间点Caspase-3 mRNA的拷贝浓度间差异有显著性意义(F=42.71,P<0.001)。复温再灌注45 min后Caspase-3 mRNA的拷贝数均显著高于此前各时间点(P<0.01)。结论DHCA中随着缺氧的加重可诱导Caspase-3 mRNA的表达,随着DHCA时间的延长,Caspase-3 mRNA表达升高。复灌后表达达最高值。

Expression of Caspase-3 mRNA in canine pallium at different time points during profound hypothermic circulatory arrest

Objective To analyze the expression of Caspase-3 mRNA in canine pallium at different time points during profound hypothermic circulatory arrest by real-time fluorescence quantitative polymerase chain reaction(PCR),to probe the impact of DHCA to neurocytic apoptosis,and to provide data for reseaching and prevention of brain damage after profound hypothermic circulatory arrest.Methods Ten healthy adult hybrid dogs were obtained to make DHCA model.At the beginning(0 minute) of extracorporeal circulation establishment and circulatory arrest,30 minutes and 60 minutes after circulatory arrest,the cerebral cortex were obtained and frozen after rewarming followed by 45 minutes reperfusion.After all the animal experiments were finished,real-time fluorescence quantitative PCR was carried out to detect Caspase-3 mRNA expression.Results Caspase-3 mRNA copy number decreased first after the establishment of extracorporeal circulation,especially after hypothermia.DHCA reached its nadir at 0 minute.As DHCA process was prolonged,Caspase-3 mRNA copy concentration at different time point were significantly different(F=42.71,P<0.001).Caspase-3 mRNA level after 45 minutes of reperfusion was significantly higher than those of other time points(P<0.01).Conclusion With the aggravation of anoxia,DHCA can induce Caspase-3 mRNA expression.As DHCA process was prolonged,Caspase-3 mRNA expression level keeps increasing and reaches the peak level after reperfusion.