心肌梗死模型大鼠心肌组织基因表达变化及缝隙连接相关基因分析

Myocardial Gene Expression and Gap Junction Gene Analysis in Rats with Myocardial Infarction Model

目的研究心肌梗死(MI)模型大鼠心肌组织基因表达的变化并具体分析缝隙连接细胞通路(pathway)的相关基因改变。方法大鼠随机分为假手术组和模型组,采用结扎左冠状动脉前降支的方法建立MI模型,假手术组只穿线,不结扎。造模1个月后,进行基因芯片检测和生物信息学分析。并采用实时荧光定量聚合酶链反应(Real-time PCR)检测心肌组织缝隙连接蛋白43(Cx43)、蛋白激酶C(PKC)、酪蛋白激酶1(CK1)的mRNA表达。结果与假手术组比较,模型组大鼠共筛选出表达上调的基因3136条,下调的基因2 222条。这些差异基因涉及的pathway包括了新陈代谢、遗传和环境信息处理、细胞的运动、生长、死亡以及细胞间通讯等众多方面。其中与心电活动相关的Cx43及其上游CK1和PKC的基因表达出现了差异。Real-time PCR提示,与假手术组比较,模型组Cx43和CK1mRNA表达显著降低(P<0.05或P<0.01),PKC mRNA表达显著增加(P<0.05)。相关分析,MI大鼠心肌组织Cx43mRNA表达与CK1mRNA呈显著正相关(r=0.765,P<0.01),与PKCmRNA呈显著负相关(r=-0.645,P<0.05)。结论 MI后心肌组织出现了复杂的基因表达变化和pathway改变,与心电活动相关的Cx43mRNA表达受CK1正调节,受PKC负调节,Cx43、CK1和PKC mRNA的异常是MI后心律失常发生的重要分子病理机制之一。

Objective To study the myocardial gene expression and gap junction pathway gene expression in rats with myocardial infarction （MI）. Methods Rats were randomly divided into sham operation group and model group. MI model of rats was established by ligating left anterior descending coronary artery. Rats in sham operation group were only punctured without ligating. One month later, gene chips were detected. Connexin 43 （Cx43）, protein kinase C （PKC） and casein kinase 1 （CK1） were measured by real - time PCR. Results Compared with sham operation group,the expressions of 3136 genes were up regulated while 2222 genes were down-regulated in model group. These differentially expressed genes involved in many pathways：metabolic, genetic, and environ- mental information processing,cell motility, growth, death and cell communication. Cx43, which related with the electrical activity of the heart, and its upstream CK1 and PKC gene expression, expressed differentially. Real - time PCR results suggested that com- pared with the sham group,Cx43 and CK1 mRNA expression were significantly lower （P〈0.05 or P〈0.01）, and PKC mRNA ex- pression was increased significantly （P〈0.05） in model group. The analysis showed that, the Cx43 and CK1 was significant positive correlation （r= 0. 765, P〈0.01）. And PKC showed a significant negative correlation with Cx43 （r= -0. 645, P%0.05）. Conclusion There were many complex changes in cardiac gene expression and pathway after MI. CK1 could up - regulate Cx43 mRNA expres- sion,and PKC could down- regulate Cx43 mRNA expression. Abnormal expression of the Cx43,CK1 and PKC mRNA is one of the molecular mechanisms of arrhythmia after MI.