左卡尼汀联合比索洛尔对心肺复苏大鼠心肌的保护作用

目的：探讨左卡尼汀与比索洛尔对心肺复苏后心肌的协同保护作用及其机制。方法： 通过建立心肺复苏大鼠模型，大鼠随机分成4组：左卡尼汀和比索洛尔联合用药组（10例），比索洛尔组（10例），左卡尼汀组（10例），安慰剂组（10例）。观察心肺复苏自主循环恢复后不同时间点各组大鼠心率及平均动脉压的变化;酶生化法检测心肌损伤标志物磷酸肌酸同工酶（CK-MB）水平;ELISA法检测氧化应激损伤指标超氧化物歧化酶（SOD）和丙二醛（MDA）的变化；Western Blot方法检测心肌BCL-2与Bax蛋白表达，以及荧光显微镜下观察溴化乙锭（EtBr）和3-硝基酪氨酸（3-NT）的变化。结果：与比索洛尔组、安慰剂组不同，左卡尼汀组各时间点心率升高（P〈0．05），平均动脉压亦有升高（P〈0．05），CK—MB和MDA水平降低（P〈O．05），BCL-2水平升高，Bax水平降低（P〈0．05），而联合用药组差异更加显著（P〈0．01）。同时发现，左卡尼汀组较安慰剂组，EtBr和3～NT水平降低，差异有统计学意义（P〈0．05）。联合用药组与安慰剂组相比，EtBr和3-NT水平的差异更加显著（P〈0．01）。结论：左卡尼汀可以通过增加上调SOD、下调MDA水平；上调BCL-2、下调Bax水平产生保护心肌作用，并且与比索洛尔有协调作用。

Protective effects of levocarnitine combined with bisoprolol on cardiopulmonary resuscitation in rats

AIM： To investigate the L-carnitine and bisoprolol on myocardium after cardiopulrnonary resuscitation in a synergistic protective effect and its mechanism. METHODS： Rats were randomly divided into 4 groups： L-carnitine and bisoprolol combined therapy group （10 cases）, the bisoprolol group （10 cases）, carnitine group （10 cases ）, the placebo group （10 cases）. Each rat heart rate and mean arterial pressure at different time points were observed. Myocardial injury markers CK-MB was detected by enzyme biochemical assay and serum oxidative stress indices SOD and MDA were detected by ELISA, and myocardial BCL-2 and Bax protein were detected by Western Blot EtBr and 3-NT were method, and the levels of tested. RESULTS. Cornpared with the bisoprolol group and the placebo group, L-carnitine group each time heart ratewas increased（P〈0.05）, mean arterial pressure was also increased（P〈0.05）, the levels of SOD and BCL-2 were increased, CK-MB, MDA and Bax levels were decreased（P〈0.05）. Compared with the placebo group, the levels of EtBr and 3- NT of L-carnitine group were decreased （P〈0. 05）, while combination group compared with the placebo group, the differences were more significant （P 〈 0.01 ）. CONCLUSION. L-carnitine can upregulate SOD and BCL-2 levels, downregulate MDA and Bax levels to produce effect on myocardium, while bisoprolol has harmonious effect.