Department of Pharmacology, Tianjin Medical University, Tianjin, PR China.
J Surg Res. 2010 Nov;164(1):162-8. doi: 10.1016/j.jss.2009.03.017. Epub 2009 Apr 16.
Transient limb ischemia induces remote early preconditioning that protects the myocardium from ischemia/reperfusion (I/R). However, it is unknown whether limb ischemia induces remote late preconditioning and whether it induces the same magnitude of cardioprotection compared with cardial ischemic preconditioning (CIP). We tested the hypothesis that late remote preconditioning of noninvasive limb ischemia (NLIP) offers the same magnitude of cardioprotection against myocardium I/R injury.
Thirty Wistar rats weighing 240-260 g each were randomly divided into three groups: I/R, CIP, and NLIP. The mean arterial pressure (MAP), heart rate (HR), ST-segment, ventricular arrhythmia, and CK-MB, cTnI, and superoxide dismutase (SOD) activity were measured after 0 and 30 min of ischemia and after 120 min of reperfusion. Myocardial infarct size, histologic examination, MMP-2, MMP-9, and TIMP-1 protein expression were determined at the end of the experiment.
Compared with I/R groups, CIP and NLIP reduced ST-segment elevation (P<0.01), decreased incidence and duration of ventricular arrhythmia (P<0.01) during ischemia, decreased CK-MB (P<0.05), and cTnI (P<0.01) activity, and increased SOD (P<0.05) activity after reperfusion. The myocardial infarct size (P<0.01) was significantly reduced, and cell injury was attenuated in the CIP and NLIP groups compared with the I/R group. MMP-2 and MMP-9 protein expression was significantly decreased in the CIP and NLIP groups (P<0.01), while TIMP-1 expression was significantly increased in the CIP and NLIP groups compared with the I/R group (P<0.01).
Remote preconditioning via NLIP has late cardioprotection against myocardium I/R injury and has a similar magnitude of cardioprotection compared with CIP in rats.
短暂性肢体缺血可诱导远程早期预处理，从而保护心肌免受缺血/再灌注（I/R）损伤。然而，目前尚不清楚肢体缺血是否会诱导远程晚期预处理，以及它是否会产生与心肌缺血预处理（CIP）相同程度的心脏保护作用。我们检验了以下假设，即非侵入性肢体缺血（NLIP）的晚期远程预处理可提供与心肌 I/R 损伤相同程度的心脏保护作用。
30 只体重为 240-260g 的 Wistar 大鼠被随机分为三组：I/R 组、CIP 组和 NLIP 组。在缺血 0 和 30 分钟以及再灌注 120 分钟后，测量平均动脉压（MAP）、心率（HR）、ST 段、室性心律失常以及 CK-MB、cTnI 和超氧化物歧化酶（SOD）活性。在实验结束时，测定心肌梗死面积、组织学检查、MMP-2、MMP-9 和 TIMP-1 蛋白表达。
与 I/R 组相比，CIP 和 NLIP 降低了 ST 段抬高（P<0.01），减少了缺血期间室性心律失常的发生率和持续时间（P<0.01），降低了 CK-MB（P<0.05）和 cTnI（P<0.01）活性，并增加了再灌注后的 SOD（P<0.05）活性。与 I/R 组相比，CIP 和 NLIP 组的心肌梗死面积（P<0.01）显著减小，细胞损伤减轻。CIP 和 NLIP 组的 MMP-2 和 MMP-9 蛋白表达显著降低（P<0.01），而 TIMP-1 表达则显著增加（P<0.01）。
NLIP 诱导的远程预处理对大鼠心肌 I/R 损伤具有晚期心脏保护作用，其保护作用与 CIP 相当。
