人参Rb组皂苷对压力负荷性心肌肥厚大鼠心室重构的影响及其作用机制

Effect of Ginsenoside-Rb on Ventricular Remodeling in Rats with Pressure Overloaded Hypertrophic Myocardium and its Mechanism

目的观察人参Rb组皂苷(G-Rb)对压力负荷性心肌肥厚大鼠心室重构的影响及其作用机制。方法结扎大鼠腹主动脉建立压力超负荷性心室重构模型。G-Rb按25,50,100mg/(kg·d)给大鼠连续灌胃6周,观察心肌形态学变化及测定血流动力学参数,血清丙二醛(MDA)含量及超氧物歧化酶(SOD)活性,血浆前列环素(PGI2)、血栓素A2(TXA2)、内皮素(ET)及血管紧张素II(AngII)含量。结果G-Rb能明显降低心室重构大鼠的心室重量及心脏系数,明显升高收缩压(SBP)、舒张压(DBP)及平均动脉压(MAP),降低左室舒张末压(LVEDP),可明显降低血清MDA含量,升高SOD活性,亦能明显降低血浆ET,AngII及TXA2含量,提高PGI2含量及PGI2/TXA2比值,与重构模型组比较,具有显著性差异(P<0.05或P<0.01)。结论G-Rb对大鼠心室重构具有保护作用,可能与其改善心室重构大鼠的左心收缩和舒张功能,增强抗氧化酶活性,减少自由基及缩血管活性物质对心肌的损伤,纠正PGI2/TXA2失衡等机制有关。

Objective To investigate the effect of Ginsenoside - Rb（ G - Rb） on ventricular remodeling in rats with pressure overloaded hypertrophic myocardium and its mechanism. Methods The model of pressure - loading ventricular remodeling was established through ligating abdominal aorta in rats. After 6 weeks of treatment by G - Rb （ with dose of 25,50 and 100 mg/kg/d i. g for 6 weeks ）, myocardial morphological and hemodynamic parameters were determined. The content of malondialdehyde （MDA） and activity of superoxide dismutase （SOD） in serum, and the contents of prostacycline （PGI2）, thromboxane A2 （TXA2 ） , endothelium （ET） and angiotensin Ⅱ （Ang Ⅱ） in plasma were also determined. Results G - Rb could significantly decrease the ventricular weight and cardiac coefficient in ventricular remodeling rats, significantly heighten systolic blood pressure （ SBP）, diastolic blood pressure （DBP） and mean arterial pressure （ MAP）, lower left ventricular end - diastolic pressure （ LVEDP）. G - Rb could also decrease the content of MDA in serum and significantly increased the activity of SOD in serum. In addition, G - Rb could decline the contents of ET, AngII and TXA2 in plasma while signficantly increase the content of PGI2 in plasma and PGI2/TXA2 ratio. Compared with model group, there was significant difference （P 〈0.05 or P 〈0.01 ） . Conclusion G - Rb has protective effects on ventricular remodeling through improving systolic and diastolic function of cor sinistrum in ventricular remodeling rats,increasing anti - oxidase activity, reducing the damage of free radicals and vasoactive substance in myocardium and correcting disequilibrium of PGI2/TXA2 in ventricular remodeling etc.