左卡尼汀预处理对体外心脏保存效果的影响

Effect of L-carnitine Preconditioning of Rats on Storage of Their Hearts ex vivo

目的探讨左卡尼汀(LCN)预处理对St.Thomas No.2液冷保存大鼠体外心脏效果的影响。方法 SD大鼠24只,随机分成3组:假手术组、缺血-再灌注组(I/R组)、左卡尼汀预处理组(预处理组),每组8只。预处理组手术前5 d每天腹腔注射左卡尼汀200 mg.kg-1。Langendorff灌注装置建立大鼠体外心脏灌注模型,I/R组、预处理组冷保存体外心脏4 h,假手术组未予停跳与冷保存,观察体外心脏心功能变化情况,比较心功能恢复、心脏复跳时间、心肌含水量及心肌组织匀浆丙二醛的变化。结果 I/R组、预处理组心脏复跳时间分别为(71.24±10.48),(69.42±9.49)s,差异无统计学意义(P>0.05);心功能各指标以假手术组最好,预处理组次之,I/R组最差(P<0.05);I/R组、预处理组和假手术组心肌含水量分别为(79.42±5.93)%,(69.27±6.52)%,(58.25±5.35)%;丙二醛含量分别为(3.57±0.47),(2.71±0.39),(0.84±0.07)nmol.mg-1,均以I/R组最高,预处理组次之,假手术组最低,均差异有统计学意义(P<0.05)。结论左卡尼汀预处理可以改善St.Thomas No.2液冷保存的大鼠体外心脏的保存效果。

Objective To observe the protective effects of L-carnitine （LCN） preconditioning on rat hearts with cold preservation in St. Thomas No. 2 solution ex vivo. Methods Isolated rat heart Langendorff model was established. Twenty-four male Sprague-Dawley rats were randomly divided into three groups （8 rats in each group）： Sham group, the hearts were not arrested;I/R group and LCN preconditioning group,in which the rats were intraperitoneally injected with distilled water or LCN for 5 days respectively, and then the hearts were preserved in St. Thomas No. 2 solution ex vivo for 4 h. The recovery of myocardial function,heart resuscitation time, malonyldialdehyde （MDA） and wet weight in myocardium were analyzed. Results After the hearts were preserved for 4 h, there were no differences in the heart resuscitation time between I/R group and LCN preconditioning group[ （71.24± 10.48） s vs. （69.42 ±9.49） s ], but LCN preconditioning group showed a better recovery of myocardial function,a lower release of MDA[ （2.71±0.39） nmol mg-1 vs. （3.57±0.47） nmol mg-1 ] （P〈0.05） ,and the less wet weight in myocardium[ （69.27±6.52）% vs. （79.42±5.93）% ] （P〈0.05） than that in I/R group. Conclusion LCN preconditioning exerts myocardial protective effects on the hypothermic preservative rat hearts ex vivo.