摘要
目的:分析心肌缺血延迟预适应能否抑制心肌缺血再灌注后心肌细胞凋亡的发生及其发生的可能原因。方法:①实验于2003-08/2004-12在中山大学中西医研究所完成。选用出生两三个月的SD大鼠32只熏雌雄不拘。②随机将大鼠分为4组:正常对照组(不做任何处理),假手术组(只穿线,不结扎),缺血再灌注组(采用经典大鼠冠状动脉结扎,缺血1h,再灌注1h),延迟缺血预处理组(采用经典大鼠冠状动脉结扎,缺血5min再灌注5min,重复3个缺血预处理,24h后,缺血1h,再灌注1h。③采用流式细胞仪测定心肌细胞凋亡率,反转录聚合酶链法检测Bcl-xlmRNA/Bcl-xsmRNA的表达情况,进行Bcl-xl的蛋白免疫印迹分析并利用免疫组织化学染色法检测大鼠心肌核因子κB亚单位P65蛋白的表达。结果:大鼠32只均进入结果分析。①大鼠心肌细胞凋亡率:心肌缺血再灌注组明显升高(P<0.01),延迟缺血预处理组明显低于缺血再灌注组(P<0.01)。②大鼠心肌Bcl-xlmRNA与Bcl-xsmRNA表达的比值:缺血再灌注组明显低于正常对照组(P<0.01),延迟缺血预处理组明显高于缺血再灌注组(P<0.01)。③大鼠心肌Bcl-xl蛋白表达:缺血再灌注组明显减少(P<0.01),延迟缺血预处理组明显高于缺血再灌注组(P<0.01)。④大鼠心肌核因子κBP65蛋白表达:延迟缺血预处理组核因子κBP65发生核转位且明显高于与缺血再灌注组(P<0.01)。结论:心肌缺血延迟预适应可以减少心肌缺血再灌注造成的细胞凋亡,此种作用发生可能与核因子κB活化后促进Bcl-xl的表达,保护线粒体功能有关。
AIM： To analyze whether delayed preconditioning （DPC） inhibit myocardial cell apoptosis after myocardial ischemia reperfusion （MIR） and the possible mechanism of occurrence.
METHODS： ①The experiment was finished in the Institute of Integrated Traditional Chinese and Western Medicine, Sun Yat-sen University from August 2003 to December 2004. Thirty-two SD rats of 2-3 months old and either sex were selected. ②AII the rats were randomized into four groups： control group （without any treatment）, sham group （only braided Without ligation）, MIR group and DPC group. The rats in MIR group underwent ischemia for 1 hour by classic coronary artery ligation and reperfasion for 1 hour. The rata in DPC group underwent three DPC cycles of 5-minute isehemia and 5-minute reperfusion, and 24 hours later, one-hour ischemia and one-hour reperfusion was performed. ③ Cell apoptosis rate was measured by flow cytometer while reverse transcription polymerase chain reaction was used to detect the expression of Bcl-xl mRNA/Bcl-xs mRNA. Bcl-xl protein immunoblot was analyzed and the expression of myocardium nuclear factor （NF-κB） subunit P65 protein was detected by immunohistochemical staining.
RESULTS： All the 32 rats entered into the result analysis. ①Cell apoptosis rate： The apoptosis rate of myocardial cells increased remarkably in MIR group （P 〈 0.01）, and markedly higher than that of DPC group （P 〈 0.01）. ②Ratio of Bcl-xl mRNA and Bcl-xs mRNA expressions： The ratio was significantly lower in MIR group than in the control group （P 〈 0.01） and DPC group （P 〈 0.01）. ③Expression of myocardium Bcl-xl protein： The expression in MIR group obviously decreased （P〈 0.01） and lower than that of DPC group （P 〈 0.01）. ④Expression of NF-κB P65 protein： The expression increased with nuclear translocation in DPC group and significantly higher than that of MIR group.
CONCLUSION： Myocardial ischemia DPC can decrease myocardial cell apoptosis caused by MIR, with the mechanism is possibly related to the activation of NF-κB, which promote the Bcl-xl expression and protect the mitochondria function.
出处
《中国临床康复》
CSCD
北大核心
2006年第20期48-50,i0001,共4页
Chinese Journal of Clinical Rehabilitation
