极化停搏液用于离体大鼠心脏保存的实验研究  

Protective effects of polarizing cardioplegia with Na^+ channel inhibitor tetrodotoxin (TTX) on isolated rat hearts

作　　者：杨双强[1] 谭松涛[1] 杨朝坤[1] 汪斌[1] 陈力[1] 

机构地区：[1]重庆医科大学临床学院胸心外科,重庆400016

出　　处：《重庆医科大学学报》2005年第3期438-441,共4页Journal of Chongqing Medical University

摘　　要：目的:研究Na+通道阻滞剂河豚毒素(tetrodotoxin,TTX)极化停搏液对离体大鼠心脏的保护作用。方法:20只Wistar大鼠随机均分入St.Thomas去极化停搏组(对照组,Ⅰ组),TTX极化停搏组(Ⅱ组)。建立离体心脏Langendorff和Neely灌注模型,搏动稳定后,灌注30min后停搏。将鼠心置于相应配伍的停搏液中,7℃保存5h后重新灌注心脏30min。观察各组心脏保存前后左心室收缩末压力(LVESP)和压力变化速率(±dp/dt)的恢复率、心肌酶漏出量、ATP含量和心肌超微结构等方面的改变。结果:恢复灌注后,TTX极化停搏组血流动力学各项指标恢复率明显高于去极化组(P<0.01),CPK和LDH漏出量(P<0.05)明显低于去极化组,ATP含量维持在较高的水平(P<0.01),心肌超微结构得到较好保护。结论:极化停搏心脏保存液对离体大鼠心脏的保护作用优于去极化停搏液,在长时间供体心脏保存中显示出明显的优势。Objective:To investigate the protective effects of polarizing cardioplegia with Na+ channel inhibitor tetrodotoxin (TTX) on isolated rat hearts.Methods:While Langendorff and Neely perfusion model were steadily established,the rat hearts(10 hearts in each group)were respectively arrested by depolarizing cardioplegia (St.Thomas No.2 solution ,STH-2)in Group Ⅰ(control group),and by polarizing cardioplegia(TTX)in GroupⅡ.These arrested hearts were preserved in corresponding cardioplegia solution respectively at 7℃ for 5 hours and then underwent 30 minute reperfusion.Pre-ischemia and post-ischemia indexes of the rat hearts were studied,including hemodynamic parameters,myocardial enzymology,ATP content,and ultrastructural changes.Results:There were no differences between two groups before myocardial ischemia.But the recovery of myocardial hemodynamic parameters during reperfusoin in GroupⅡwas better than that in GroupⅠ(P<0.01).The leakage of CPK and LDH in GroupⅡwas less than that in GroupⅠ(P<0.05).The content of ATP in GroupⅡkept relatively higher level after reperfusion.Myocardial ultrastructures were better protected in polarizing cardioplegia group.Conclusion:Na+ channel inhibitor TTX could prevent myocardial ischemia/reperfusion injuries caused by intracellular Na+-overload and Ca 2+ -overload,and reduce the consumption of energy by arresting heart under polarizing condition.Polarizing cardioplegia(TTX) plays more effective role than depolarizing cardioplegia(STH-2) in long-term myocardial preservation of donor rat hearts.

关 键 词：极化停搏 Na^+通道阻滞剂 心肌保护 心脏保存 

分 类 号：R654.2[医药卫生—外科学]