Effects of ginsenoside-Rb on cardiac hemodynamics and oxygen metabolism in dogs with acute myocardial infarction

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.