脂质胞壁酸诱导的延迟预适应对大鼠离体心脏缺血/再灌注后心功能的作用

目的 探讨脂质胞壁酸(LTA)诱导的延迟预适应对大鼠离体心脏缺血／再灌注(I/R)后心功能的作用。方法 采用大鼠离体心脏Langendorff灌流模型，腹腔注射LTA(1mg/kg)后24h，观察其对离体心脏停搏4h后和心脏停灌30min后再灌注30min及60min时左室发展压(LVDP)、左室压最大上升速率( dp／dtmax)、左室压最大下降速率(-dp／dtmax)及冠脉流量(CF)的影响。结果 LTA预适应能显著改善再灌注后心功能，而同时给予LTA和非选择性一氧化氮合酶抑制剂L-NG-硝基精氨酸甲酯(L-NAME)能取消预适应对心功能的改善效应。结论 LTA预适应能显著改善心脏I／R所致的心功能障碍，而内源性NO在介导LTA预适应中发挥必不可少的作用。

Effects of Lipotekhoic Acid Induced Delayed Preconditioning on Cardiac Function after Ischemia-Reperfusion Injury in Isolated Rat Hearts

Objective To study the potential effects of lipoteichoic acid(LTA)induced delayed preconditioning on cardiac function after ischemia-reperfusion(I/R)injury in isolated rat hearts.Methods The rats were pretreated with LTA(1 mg/kg,ip.)24h before the experiment,and the isolated hearts were subjected to 30 min of no-flow normothermic global ischemia or arrested by cardioplegic solution and stored in Eurocollin's solution for 4h by the Langendorff method,and to evaluate coronary flow(CF),left ventricular developed pressure(LVDP),maximal rate of left ventricular developed pressure(+dp/dt max) and maximal rate of left ventricular decline pressure(-dp/dt max)at 30 min,60 min of reperfusion.Results Pretreated with LTA significantly improved the recovery of cardiac function,and the improved effects on cardiac function were abrogated by pretreatment with L nitroarginine methyl ester(L-NAME)and LTA.Conclusion LTA could signficantly improved the recovery of cardiac function after ischemia/reperfusion iniury,and endogenous NO play an essential role as an effector of delayed PC induced by LTA.