依那普利预处理对心肌内源性保护机制的影响

目的探讨依那普利预处理对心肌内源性保护机制的影响。方法用依那普利预处理大鼠心肌48h,心脏低温保存6h,Langendorff模型再灌注,观察心功能及磷酸肌酸激酶同工酶(CK-MB)变化。结果依那普利预处理组左心室收缩-舒张压差、+dp/dt、冠状动脉流量(CF)等保存6h后功能恢复百分率明显高于、心肌CK-MB漏出明显低于非依那普利预处理组。依那普利预处理同时加用蛋白激酶C(PKC)抑制剂多粘菌素B(PMB),保存后功能恢复降低至非依那普利预处理组水平;单独用PMB预处理,对心功能恢复无影响。结论依那普利预处理大鼠心肌可以减轻心肌缺血损害,改善心脏保存后功能恢复。其心肌保护作用机制可能与PKC活性有关。

Effect of enalaprilat preconditioning on myocardial endogenesis protect mechanism

Objective: To investigate the effect of enalaprilat preconditioning on myocardial endogenesis protect mechanism. Method:Rats were pretreated with enalaprilat for 48 hours. Isolated rat heart were stored for 6 hours at 0 C. At the end of preservation period,the hearts were reperfused with Langendorff model. Heart function and CK-MB were assessed after 30 min reperfusion. Result: Recovery percent rate of post- storage function in untreated hearts was:DP, 58%; + dp/dt, 67%; CF, 81% of control. Enalaprilat preconditioning group enhenced DP recovery to 75%; +dp/dr,88%; CF,106% of control(P＜0.05). Hearts were pretreated with enalaprilat and PKC inhibitor polymyxin B(PMB),post-storage function returned to the untreated level. CK- MB leakage in enalaprilat preconditioning group decreased signigicantly compared with untreated group ( P＜ 0. 001). Pretreatment with PMB alone did not have any effect on post- storage functional recovery.Conclusion:Enalaprilat preconditioning may relief myocardial ischemic lesion and improve post- storage recovery of cardial function. Mechanism of enalaprilat preconditioning may be related to PKC activity.