目的：探讨在体条件下，非创伤性双下肢缺血后处理是否具有减轻心肌缺血/再灌注损伤（IR）的作用。方法：采用SD大鼠心肌缺血/再灌注模型，应用Evan’s蓝、TTC染色，观察非创伤性双下肢缺血后处理对心梗面积(infarction size IS)的影响；并应用生化检测及免疫组化技术，研究非创伤性双下肢缺血后处理磷酸肌酸激酶（creatine kinase CK）、丙二醛（malondialehyde MDA）、超氧化物歧化酶（superoxide dismutase SOD）对大鼠心肌缺血/再灌注损伤的作用。结果：与缺血/再灌注组比较，非创伤性双下肢缺血后处理组的IS、MDA含量显著降低( P<0.01)，而SOD含量明显升高(P< 0.01)，而CK值无显著性差异(P >0.05)。结论：非创伤性双下肢缺血后处理能有效降低心肌缺血/再灌注梗塞面积,其机制可能与减少自由基损伤和抗氧化作用加强有关。
关键词： 缺血 预处理 再灌注 心肌梗塞
【Abstract】Objective: To observe protective effects of non-wound legs ischemic postconditioning on ischemia/reperfusion myocardial injury in rats, investigate the effects of postconditioning on ischemia/reperfusion myocardial injury. Methods: 30 Sprague-Dawley rats divided randomly into four groups and reproduce the model of ischemia/reperfusion myocardial injury. We measured the infarction sizes (IS) with Evan’s and TTC dye, examine creatine kinase （CK）, malondialehyde （MDA）and superoxide dismutase （SOD） in our study. Results: Compare with the ischemic reperfusion group, the IS and the concentration of MDA in plasma of non-wound legs ischemic postconditioning were lower, p<0.01, and the concentration of SOD in plasma of non-wound legs ischemic postconditioning were higher than that of the ischemic reperfusion group. Compare with the ischemic reperfusion group, there are no significance in ischemic reperfusion group and non-wound legs ischemic postconditioning group, p>0.05. Compare with the ischemic preconditioning group, the IS and the concentration of MDA and SOD in plasma are no significance between the ischemic preconditioning and non-wound legs ischemic postconditioning groups, p>0.05. Conclusion: Non-wound legs ischemic postconditioning has the same protective effects as ischemic preconditioning on decreasing the infarction size, the potential mechanism are that decreased oxygen free radical injury and strengthened the action of antioxidization.
1986年，由Murry等[1]首次提出缺血预处理概念(ischemic preconditioning，IPC)，即冠状动脉反复短暂的缺血可以使心肌在后续更长时间的缺血中得到保护。近年来，有研究证明肾动脉、肠系膜动脉及股动脉等远距非心脏缺血预处理对心肌亦有保护作用[2~5]，亦有报道非创伤性双下肢缺血预处理对心肌有保护作用[6]。本文旨在探讨在体情况下，非创伤性双下肢缺血后处理对大鼠缺血/再灌注损伤的保护作用。
1 材 料 和 方 法
1.1 实验动物：健康SD大鼠24只，体重250±30g，购自贵阳医学院实验动物中心，雌雄不拘，随机分为4组，每组6只。
1.2动物模型制备及分组
1.2.1 动物模型制备：实验大鼠以3.6%水合氯醛腹腔麻醉(10ml/kg)，麻醉后固定于鼠台。分离气管，气管插管，连接微型动物呼吸机(浙江大学医疗器械厂生产)支持呼吸，频率50~60次/分，潮气量4~6ml/次将针形电极插入四肢皮下，连接心电图机(浙江大学医疗器械厂生产)，记录标准导
