高渗灌注对大鼠心肌缺血-再灌注损伤的影响

Effects of hypertonic perfusion on ischemia-reperfusion injury in isolated rat hearts

目的在Langendorff灌注模型上研究高渗灌注对大鼠心肌缺血-再灌注损伤耐受性的影响。方法健康雄性SD大鼠20只,随机分为对照组(C组)和高渗氯化钠灌注组(H组),每组10只。腹腔注射戊巴比妥钠(60mg/kg)麻醉后快速取出心脏接上主动脉插管置于Langendorff装置上,Krebs-Henseleit缓冲液平衡逆行灌注20min。待HR及冠脉流量平稳后夹闭灌注道进行全心热缺血30min,复灌40min。通过多道生理记录仪持续监测HR、左心室压峰值(LVPSP)、左室舒张末压(LVEDP)和左室压力最大上升/下降速率(±dp/dtmax),计算左室发展压(LVDP=LVPSP-LVEDP),用左室发展压与心率乘积(RPP=LVDP×HR)表示左室做功。结果同C组比较,H组再灌注心功能恢复显著改善:HR[(89.5±7.8)%vs(57.9±4.6)%,P<0.05]、LVPSP[(83.5±7.8)%vs(62.9±4.1)%,P<0·05]、RPP[(66.3±9.4)%vs(36.4±3.8)%,P<0.05]、冠脉流量(CF)[(61.2±8.9)%vs(41.9±4.0)%,P<0.05]、+dp/dtmax[(60.4±6.9)%vs(22.9±3.4)%,P<0.01]和-dp/dtmax[(69.5±6.6)%vs(34.3±3.3)%,P<0.01];肌酸激酶(CK)释放量显著降低(P<0.05)。结论高渗灌注减轻心肌缺血-再灌注损伤。

Objective To evaluate the effects of hypertonic perfusion on ischemia-reperfusion injury in isolated rat hearts. Methods Twenty healthy male SD rats were randomly divided into control group （group C） and hypertonic perfusion group （group H）with 10 rats each. Isolated hearts were Langendorff-perfused at a constant pressure of 80 rnmHg. After 20 rain equilibration,the rats in group C and H were perfused with normal-tonic or hypertonic persusate for another 20 rain respecticely. Then all hearts were subjected to 30 min global ischemia followed by 40 rain reperfusion. Left ventricular pressure （LVP）, left ventricular end-diastolic pressure （LVEDP） and maximum rates of increase and decrease in left ventricular pressure （±dp/dtmax） were recorded with the computerized data acquisition system throughout the experiment. Coronary outflow during reperfusion was collected for determination of creatine kinase （CK） release. Results Cardiac function after reperfusion recovered better in group H than that in group C[HR（89.5%±7.8%vs57.9%±4.6%,P〈0.05）、LVP（83.5%±7.8%vs62.9%±4.1%,P〈0.05）、RPP（66.3%±9.4%vs36.4%±3.8%,P〈0.05）、CF（61.2%±8.9%vs41.9%±4.0%,P〈0.05）,＋dp/dtmax（60.4%±6.9%vs22.9%±3.4%,P〈0.01）,and-dp/dtmax（69.5%±6.6%vs34.3%±3.3%,P〈0.01）],CK release during reperfusion reduced significantly in group H compared with that in group C[（576±81 vs 884±125）U/g heart weight,P〈0.05]. Conclusion Hypertonic perfusion reduced myocardial ischemia-reperfusion injury in SD rats.