心肌缺血预适应对血管内皮生长因子水平的影响及其临床意义

目的：探讨心肌缺血预适应（IP）对围术期血浆血管内皮生长因子（VEGF）水平的影响及其临床意义,方法：20例择期心脏手术患者随机均分为两组,对照组常规建立体外循环（CPB）,阻断升主动脉后经主动脉根部顺灌4℃St THomas′停博液,IP组实施3分钟缺血,5分钟再灌注后余同对照组,于不同时点取桡动脉血2ml,采用酶联免疫吸附（ELISA）法测定VEGF浓度,结果：对照组在主动脉阻断30分钟时VEGF浓度开始上升,术后6小时达到高峰（P＜0．01）,24小时仍明显高于正常（P＜0．01）,IP组在IP结束时VEGF浓度开始上升,术后6小时达到高峰（P＜0．01）,24小时仍明显高于正常（P＜0．01）,IP组在IP结束时VEGF水平迅速升高（P＜0．01）,主动脉阻断30分钟时达高峰（P＜0．01）,主动脉开放30分钟时开始下降,术后24小时已基本降至正常,结论IP可诱导VEGF生成增加,这可能也是IP的心肌保护机制之一。

Changes of plasma vascular endothelial growth factor (VEGF) contents induced by myocardium isch-emic preconditioning (IP) ard its clinical significance

Objective To investigate the changes of plasma VEGF concentration induced by myocardium IP. Methods 20 congenital heart disease patients were divided into 2 groups randomly. Control group ( n =10) received intermittent cold crystalloid cardioplegia perfusion and cardiopulmonary bypass (CPB). IP group ( n =10) received 3 minutes of aorta clamping and followed by 5 minutes of declamping, and then intermittent cold crystalloid cardioplegia perfusion and regular CPB. Plasma VEGF contents were detected at different time points. Results In control group, the plasma VEGF levels began to increase at 30 minutes after aorta clamping and reached the highest level at 6 hours post-operation ( P <0.01). In IP group, the plasma VEGF concentrations rapidly elevated shortly after IP and reached the highest level at 30 minutes after aorta clamping ( P <0.01), and appeared to decrease afterwards. 24 hours post-operation, the plasma VEGF contents in IP group were nearly normal. Conclusion Myocardial IP induced the increasing of VEGF production and this may play a role in myocardial protection of IP.