顿抑心肌中腺嘌呤核苷酸转运体基因的动态表达

Dynamical expression of the genes of adenine nucleotide translocator during myocardial stunning

目的:通过观察大鼠心肌缺血再灌注模型中腺嘌呤核苷酸转运体(adeninenucleotidetranslocator,ANT)的动态表达情况,初步探讨顿抑心肌中ANT各单体的表达变化对心肌能量代谢的影响及其与心肌细胞凋亡的联系。方法:实验于2003-11/2004-04在解放军南京军区南京总医院心脏内科实验室和动物实验中心完成。将60只雄性SD大鼠随机分为对照组(n=8)和手术组(n=52)。将手术组大鼠冠状动脉左前降支结扎闭塞20min,然后剪断结扎线再灌注。按缺血后再灌注4h、1,3,7d4个时相分4组进行观察(n=13)。用反转录-聚合酶链反应计算机凝胶成像分析系统测定心肌中ANT1,ANT2mRNA相对含量。对照组大鼠不干预。结果:60只大鼠进入结果分析。①ANT1mRNA含量在缺血后再灌注4h达高峰(P<0.05)。在再灌注1d开始降低,再灌注3d时明显下降(P<0.05),逐渐恢复到对照水平(P>0.05),再灌注7d的结果与再灌注3d相似。②ANT2mRNA含量在再灌注4h时无明显增加,在再灌注1d开始升高并达峰值(P<0.01),从再灌注3d开始明显下降(P<0.01),并恢复到对照水平(P>0.05)。再灌注7d结果与再灌注3d相似。结论:①顿抑心肌中ANT的含量增加,顿抑心肌中能量短缺的现象可在缺血后再灌注3d内得以纠正。②心肌缺血可以导致细胞凋亡,心肌细胞凋亡主要发生在缺血再灌注早期(24h内),而且在体内存在时间短暂(缺血后再灌注3d内恢复)。

AIM： To investigate the effect of the solitary dynamical expression of adenine nucleotide translocator （ANT） on myocardial energetic metabolism during myocardial stunning and the relationship between myocardial apeptosis and the dynamical expression of ANT by observing the dynamical expression of ANT in myocardial ischemic reperfusion models of rats. METHODS： The experiment was conducted in the laboratory of the Department of Cardiology and the Animal Experimental Center of Nanjing General Hospital of Nanjing Military Area Command of Chinese PLA from November 2003 to April 2004. Sixty SD rats were randomly divided into control group （n=8） and operated group （n=52）. The rats in the operated group were treated with 20 minutes left anterior descending coronary artery occlusion, and then 4 hours, 1 day, 3 days and 7 days reperfusion as myocardial stunning model （n=13）. The relative mRNA content of ANT1 and ANT2 in myocardium was detected by reverse transcription-polymerase chain reaction （RT-PCR） and gel electrophoresis imaging. The rats in the control group were not intervened, RESULTS： Sixty rats were involved in the result analysis. ①The relative mRNA content of ANT1 got up to the peak at the 4^th hour after myocardial ischemia/reperfusion （P 〈 0.05）. Reperfusion for 1 day it became to decrease, and from the third day after reperfusion, the mRNA content of ANT1 decreased obviously （P 〈 0,05） and there was not significant difference compared with that in control group （P 〉 0.05）, and the result after reperfusion for 7 days was similar to that for 3 days. ②The relative mRNA content of ANT2 got to the maximum on the first day after reperfasion （P 〈 0.01） while at the 4^th hour there was insignificance increase. From the＇ third day after reperfusion, the relative mRNA content of ANT2 began to decrease （P 〈 0.01 ） and had not significant statistical difference compare with that in controls （P 〉 0,05） , and the result after reperfusion＇for 7 days was similar to that for 3 days. CONCLUSION： ① The ANT content increased during myocardial stunning and the energetic lack can be improved within 3 days after myocardial ischemia/repedusion. ②Myocardial ischemia and reperfusion can induce myocardical apoptosis, which occurs mainly at the early stage after myocardial ischemia/reperfusion （within 24 hours）, and existed shortly in vivo （recovery within 3 days after ischemia/reperfusion）.