摘要
目的:探讨吗啡后处理对兔心肌缺血再灌注损伤的保护作用及其机制。方法:32只兔随机分为4组,假手术组:开胸后仅行左冠脉套线而不阻断160 min;缺血再灌注组:行左冠状动脉前降支阻断40 min,再灌注120 min;缺血后处理组:结扎冠状动脉前降支40 min,再通30 s,结扎30 s,重复3次,再灌注120 min;吗啡后处理组:开放左冠状动脉即刻1 min内予以静推吗啡1.0 mg/kg,再灌注120 min。各组分别于左冠前降支阻断前20 min、阻断后20 min、40 min、心肌再灌注1 h和2h 5个时点抽取颈内动脉血,测定血清中肌钙蛋白(cTnI)含量;再在灌注末抽血离心测定超氧化物歧化酶(SOD)、丙二醛(MDA),测定心肌梗死面积。结果:与缺血再灌注组相比,缺血后处理组和吗啡后处理组再灌注各个时间点cTnI均降低(P<0.05);缺血后处理组和吗啡后处理组心肌梗死面积均小于缺血再灌注组(P<0.05);缺血后处理组和吗啡后处理组血清中SOD的活性高于缺血再灌注组,MDA的含量低于缺血再灌注组(P<0.05)。结论:吗啡后处理具有类似缺血后处理的心肌保护作用,其机制可能是通过减少氧自由基的生成,增强心肌抗氧化能力有关。
Objective： To investigate the protective effects of morphine postconditioning on myocardial ischemia-reperfusion （I/R）injury and the potential mechanisms in rabbits. Methods： Thirty-two New Zealand male white rabbits were randomly assigned into 4 groups：Group 1 （Sham）,Group 2 （I/R）,Group 3 （ischemie postconditioning）,Group 4 （ischemia and morphine posteonditioning）. Group 1 was perfused for 160 rain;Group 2 underwent 40 rain ischemia and 120 rain reperfusion; Group 3 underwent three cycles of 30 s reperfusion and 30 s left anterior descending coronary artery re-occlusion immediately after 40 min ischemia and before 120 min reperfusion;Group 4 was given morphine 1.0 mg/kg immediately after 40 rain ischemia in 1 min and before 120 min reperfusion. Blood samples were taken from arterial line at 20 min before occlusion, 20 min after occlusion, 40 min after occlusion, 1 h after reperfusion and 2 h after reperfusion for determination of the plasma levels of cardiac troponin I （cTnI）. At the end of the reperfusion,infarct size （IS） and area at risk were defined by Evans and TTC staining. Plasma SOD activity and MDA were determined at the end of reperfusion. Results. The levels of cTnI were significantly lower during reperfusion in the two postconditioning groups than those in I/R group. The plasma MDA content was significantly lower and SOD activity was significantly higher in the two postconditioning groups than those in I/R group,but there was no difference between two postconditioning groups. Morphine significantly reduced infarct size of the left ventricular area at risk as compared with I/R group （P 〈 0. 05）. Conclusions： Morphine postconditioning is as effective as ischemic postconditioning in the protection of myocardium against I/R injury in rabbits. Decrease in oxygen free radicals and increased antioxidant activity might be involved in its mechanism.
出处
《浙江大学学报（医学版）》
CAS
CSCD
北大核心
2009年第5期521-524,530,共5页
Journal of Zhejiang University(Medical Sciences)
