局部灌注和全心灌注对兔缺血再灌注心肌保护作用的对比研究

Comparing the effects of local and whole cardiac perfusion of adenosine on rabbit myocardium following ischemia- reperfusion injury

目的研究经左冠状动脉回旋支局部灌注腺苷对兔缺血再灌注心肌损伤模型的保护作用,以及这一作用与全心脏灌注腺苷的区别。方法实验将麻醉后的家兔分为三组各10只:A组即对照组,B组为经回旋支局部灌注腺苷组,C组为经右侧颈总动脉全心脏灌注腺苷组。各组均建立局部心肌缺血模型。30min后,A组实现缺血心肌再灌注;B组向缺血区再灌注含腺苷浓度为10μmol/L的动脉血;C组全心灌注含腺苷浓度为10μmol/L的动脉血。收集血流动力学、心电图、心肌酶CK-MB、髓过氧化物酶(MPO)、电镜等指标。结果与对照组相比,局部灌注组和全心灌注组都能够明显改善缺血再灌注后心肌的收缩和舒张功能(P<0.05),并且局部灌注组的舒缩功能要好于全心灌注组(P<0.05)。髓过氧化物酶活性也是同样结果。两组CK-MB漏出浓度和心肌含水量与对照组相比均有明显减低(P<0.05),但是局部灌注和全心灌注之间差异无统计学意义。电镜超微结构显示两个腺苷灌注组的心肌结构要好于对照组。结论局部灌注腺苷和全心脏灌注腺苷都能够起到保护心脏、减轻缺血-再灌注损伤和抗心肌坏死的作用。但局部灌注组在心肌舒缩功能和MPO活性两方面与全心脏灌注组的显著性差异能够说明前者在心肌保护方面具有更强的优越性。

Objective The purpose of this study is to compare the effects of local and whole adenosine perfusion on rabbit myocardium following ischemia-reperfusion injury. Methods Thirty rats were subjected to ligation of left circumflex coronary artery to establish AMI and random divided into three groups, each group with 10 rats. The control group was perfused blood not containing adenosine. The local cardiac perfusion group was perfused blood containing 10 μmol/L adenosine through left circumflex coronary artery, while the whole cardiac perfusion group was perfused blood containing 10 μmol/L adenosine through right carotid. Myocardial indexes were detected, such as myocardial contractility, ECG, CK-MB in blood, MPO in myocardial tissue homogenate, and myocardial uhrastructure observed from electron microscope. Results Local and whole cardial perfusion of adenosine improved myocardial contractility and relaxation （±dp/dtmax） as compared with control group during reperfusion period （P〈0.05） ,while the contractility and relaxation of local perfusion group is better than those of the whole perfusion group （P〈0.05）. So was the MPO activity in myocardial tissue homogenate. CK-MB leakage and myocardial water content were much remarkably reduced in both perfusion groups than control group （P〈0.05）, but there was no significant difference between perfusion groups. Myocardial electron microscope observation showed that myocardial ultra structure of both perfusion groups was better than that of control group. Conclusion This experiment suggests that both local and whole perfusion of adenosine have cardio-protective effects and attenuate ischemic-reperfusion injury and necrosis distinctly. Local adenosine perfusion has some superiority to whole adenosine perfusion in myocardial contractility,relaxation functions and MPO activity.