局部缺血"预处理"诱导家兔相邻非缺血心肌热休克蛋白70基因表达

目的：研究兔心局部缺血“预处理”后，局部缺血和相邻非缺血心肌热休克蛋白７０（ＨＳＰ７０）ｍＲＮＡ的水平变化。方法：提取心肌组织总ＲＮＡ，用ＨＳＰ７０探针进行斑点杂交。结果：缺血预处理组的缺血区和非缺血区ＨＳＰ７０ｍＲＮＡ表达水平均显著高于对照组相应部位（Ｐ＜００５），而每组内的缺血区及非缺血区间无显著差异（Ｐ＞００５）。结论：局部缺血“预处理”后，缺血和非缺血区两处心肌的内反应呈“一致性”；缺血预处理对心肌的保护作用可能与ＨＳＰ７０的合成增多有关。

Transcription of HSP70 gene induced by regional ischemic preconditioning in remote virgin myocardium of rabbits

AIM: To define whether regional ischemic preconditioning also increases HSP 70 mRNA level in remote virgin myocardium. METHODS:13 rabbits were randomly assigned to either a 'preconditioned' group ( n=6 ) which underwent 4 episodes of 5-min occlusion and reperfusion followed by 60-min reperfusion or a sham -operated control group ( n=6 ). Then 24 tissue samples from the myocardium perfused by LAD, immediately below the snares, and the remote virgin myocardium were frozon rapidly. HSP 70 mRNA was measured by Dot blotting.RESULTS:Four cycles of 5-min ischemia and reperfusion resulted in significant increase( P<0.05 ) of HSP 70 mRNA in both ischemic and nonischemic myocytes compared with the controls, but HSP 70 mRNA levels from both positions of the hearts were similar in every group. CONCLUSION:The heart might be activated as a whole' in some way after regional ischemic preconditioning(PC), and the protection effect of PC might be related to the increased synthesis of HSP 70 .