Department of Pharmacology, College of Basic Medical Sciences, Tianjin Medical University, Tianjin, China.
J Surg Res. 2012 May 15;174(2):e47-54. doi: 10.1016/j.jss.2011.10.015. Epub 2011 Nov 8.
Limb ischemic preconditioning (LIPC) induced by prior brief periods of ischemia-reperfusion (I/R) to a limb is a simple and convenient strategy to protect the heart from I/R injury. However, the optimal strategy is unknown. Therefore, the present study was conducted to test the most effective method of LIPC for clinical applications.
Male Wistar rats were randomized into the following groups: control groups, consecutive LIPC groups, intermittent LIPC groups. The control groups, including the sham operation group, the ischemia-reperfusion (I/R)-control group, the myocardial ischemic preconditioning (MIPC) group, the femoral artery ischemic preconditioning (FAIP) group; the consecutive LIPC groups, including continuously using for 1 d, 3 d, and 7 d groups. Each group was tested on the first, third, and fifth d after LIPC; intermittent LIPC groups, including 1-d LIPC + 1-d interval group, 1-d LIPC + 2-d interval group, 3-d LIPC + 3-d interval group, 3-d LIPC + 5-d interval group. Left ventricular function, incidence of ventricular arrhythmia, and ST-segment were measured during I/R. Myocardial infarct size, creatine kinase isoenzyme MB (CK-MB), and cardiac troponins I (cTnI) were determined at the end of experiment.
Compared with the I/R-controls, the MIPC, FAIP, continuous LIPC for 3 and 7 d and 1-d LIPC + 1-d interval groups showed amelioration of ventricular arrhythmia, improved left ventricular function, lower ST-segment elevation, reduced myocardial infarct size, decreased CK-MB, and cTnI activity. The protective effects of LIPC persisted for 72 h.
Our results suggest that a 1-d LIPC + 1-d interval provides optimal cardioprotection from I/R.
肢体缺血预处理（LIPC）通过短暂的缺血再灌注（I/R）诱导肢体，可以保护心脏免受 I/R 损伤，是一种简单方便的策略。然而，最佳策略尚不清楚。因此，本研究旨在检验 LIPC 的最有效方法用于临床应用。
雄性 Wistar 大鼠随机分为以下几组：对照组、连续 LIPC 组、间歇 LIPC 组。对照组包括假手术组、I/R 对照组、心肌缺血预处理（MIPC）组、股动脉缺血预处理（FAIP）组；连续 LIPC 组包括连续使用 1 d、3 d 和 7 d 组。每组在 LIPC 后的第 1、3 和 5 天进行测试；间歇 LIPC 组包括 1-d LIPC + 1-d 间隔组、1-d LIPC + 2-d 间隔组、3-d LIPC + 3-d 间隔组、3-d LIPC + 5-d 间隔组。在 I/R 期间测量左心室功能、室性心律失常发生率和 ST 段。实验结束时测定心肌梗死面积、肌酸激酶同工酶 MB（CK-MB）和心肌肌钙蛋白 I（cTnI）。
与 I/R 对照组相比，MIPC、FAIP、连续 LIPC 3 和 7 d 以及 1-d LIPC + 1-d 间隔组心律失常得到改善，左心室功能改善，ST 段抬高降低，心肌梗死面积缩小，CK-MB 和 cTnI 活性降低。LIPC 的保护作用持续 72 h。
我们的结果表明，1-d LIPC + 1-d 间隔提供了最佳的 I/R 保护。
