缺血预处理对在体大鼠缺血再灌注损伤心肌ICAM-1mRNA表达的影响

ISCHEMIC PRECONDITIONING AFFECTS ICAM-1mRNA EXPRESSION IN ISCHEMIA REPERFUSION INJURED MYOCARDIUM IN VIVO

目的 利用大鼠在体心肌缺血再灌注模型 ,应用原位杂交来观测ICAM - 1mRNA在各组大鼠心肌中的表达 ,以了解缺血预处理对ICAM - 1表达的影响 ,并探讨其机制。方法 雄性Sprague -Dawley大鼠 60只 ,随机分为心脏缺血 /再灌注组 (IR ,n =2 0 )、预处理组 (IPC ,n =2 0 )及假缺血组 (Sham ,n =2 0 )。术毕抽血 5ml ,查血清SOD ,MDA。应用原位杂交方法检测ICAM - 1mRNA在各组大鼠心肌中的表达。结果 再灌注 2hIR组血清MDA较Sham组及IPC组有明显升高 (P <0 .0 1) ,IR组血清SOD较Sham组及IPC组有明显降低 (P <0 .0 1)。再灌注 2h后 ,IR组心肌ICAM - 1mRNA表达较IPC组明显增加 (P <0 .0 1)。结论 缺血预处理可有效的保护缺血再灌注心肌 ,同时对于心肌ICAM - 1mRNA表达具有下调作用 ,且后者有可能是前者的原因。

Objective Establishing ischemia-reperfusion injury model of rat myocardium in vivo,we demonstrated the cardioprotective effect of ischemic preconditioning and its effect on the expression of ICAM-1mRNA by means of in situ hybridization method.Methods Sixty Sprague-Dawley rats were randomly divided into three groups:ischemia-reperfusion group(IR,n=20),IPC group(n=20)and Shamgroup(n=20).Arterial blood samples drawn at the end of the reperfusion period were collected to measure SOD and MDA.We detected ICAM-1mRNA expression with in situ hybridization method.Results MDA in serum of IR group increased significantly compared with that in Sham and IPC groups after 120 min reperfusion ( P <0.01).But SOD in serum of IR group decreased significantly compared with that in Sham and IPC groups after 120 min reperfusion ( P<0.01 ).ICAM-1mRNA in IR group increased significantly compoured with that in Sham and IPC groups.Conclusion In this study, we demonstrated that IPC preserves ischemia and reperfusion injured myocardium and downregulates the expression of ICAM-1mRNA.The downregulation of ICAM-1 expression may be the cause of heart protection.