目的研究人参 Rb组皂苷对急性心肌梗死犬心脏血流动力学及氧代谢的影响。方法采用麻醉开胸犬结扎左冠状动脉前降支 (L AD)产生急性心肌梗死模型，测定心脏血流动力学、冠状循环及氧化代谢等参数。结果人参 Rb组皂苷 2 5，5 0 mg/ kg经十二指肠给药，对结扎 L AD产生急性心肌梗死 6 h犬，均能明显减慢心率 (HR)，降低 MAP、+dp/ dt_max、L VEDP、L VWI及 TPR，增加 SI及- dp/ dt_max，亦能明显增加冠脉血流量，降低冠脉血管阻力，并明显降低心肌耗氧量、心肌氧摄取率及心肌耗氧指数。结论人参 Rb组皂苷主要通过减少左室作功，降低心肌耗氧量，增加缺血心肌供血等环节发挥抗心肌缺血作用。

Object To study the effects of ginsenoside Rb (G Rb) on the cardiac hemodynamics and oxygen metabolism in dogs with acute myocardial infarction.Methods The parameters of cardiac hemodynamics, coronary circulation and oxygen metabolism were determined by using the model of acute myocardial infarction produced by ligation of LAD in the anaesthetized open chest dogs. Results In dogs pretreated with G Rb by duodenal route at doses of 25, 50 mg/kg to induce acute myocardial infarction for 6 h by ligation of LAD, the heart rate (HR) was slowed, the mean arterial pressure (MAP), the maximum rising rate of left ventricular pressure (+dp/dt_max ), left ventricular end diastolic pressure (LVEDP), left ventricular work index (LVWI) and total periphery resistance (TPR) were reduced, whereas stroke index (SI) and the maximum decline rate of left ventricular pressure (-dp/dt_max ) were increased. In addition, the coronary blood flow (CBF) was increased and coronary vascular resistance (CVR) was decreased significantly. Meanwhile the cardiac oxygen consumption, myocardial oxygen utilization rate and cardiac oxygen consumption index were also decreased. Conclusion G Rb has protective effects on acute myocardial ischemia by reducing ventriculus sinister cordis function, decreasing cardiac oxygen consumption and increasing myocardial blood flow, etc.

吉林省科委新药基金项目(98220)