人参皂苷Rb_3对大鼠实验性心室重构的影响及其机制

Effect of ginsenoside Rb_3 on experimental ventricular remodeling in rats and its mechanism

目的:研究人参皂苷Rb3(G-Rb3)对大鼠实验性心室重构的保护作用并探讨其作用机制。方法:结扎大鼠左冠状动脉前降支4周建立心肌梗死后心室重构模型。将结扎成功大鼠随机分成假手术组(仅置缝线不结扎冠脉)、模型组、G-Rb3组及卡托普利组,假手术组及模型组腹腔注射生理盐水2mL·kg-1·d-1,G-Rb3组腹腔注射G-Rb320mg·kg-1·d-1,卡托普利组灌胃卡托普利100mg·kg-1·d-1。给药4周后观察各组大鼠心脏形态学、组织病理学及血流动力学相关指标,测定血清丙二醛(MDA)含量、超氧化物歧化酶(SOD)及谷胱甘肽过氧化物酶(GSH-Px)活性,血浆内皮素(ET)含量,血浆及心肌血管紧张素Ⅱ(AngⅡ)含量。结果:与模型组比较,G-Rb3组大鼠的心率、心室脏器指数及左心室舒张末压(LVEDP)明显下降(P<0.01),平均动脉压(MAP)、左心室内压最大上升及下降速率(±dp/dtmax)明显升高(P<0.01)。与模型组比较,G-Rb3组大鼠血清MDA含量、血浆ET含量、血浆及心肌AngⅡ含量明显下降(P<0.01),血清SOD及GSH-Px活性明显升高(P<0.01)。结论:G-Rb3对大鼠实验性心室重构具有明显保护作用,可能是通过抑制肾素血管紧张素系统,减少缩血管物质对心肌的损害以及增强心肌抗氧化能力实现的。

Objective To study the effect of ginsenoside Rb3 （G-Rb3）on experimental ventricular remodeling in rats and investigate its mechanism.Methods The ventricular remodeling model was induced by myocardial infarction in rats of left anterior descending coronary occulusion.The Wistar rats were divided into 4groups：sham operation group,remodeling model group,G-Rb3 group,and captopril group.The rats in sham operation group and remodeling model group were treated with normal sodium （with 2mL·kg-1·d-1i.p）.The rats in G-Rb3group were treated with G-Rb3 （with 20mg·kg-1·d-1 i.p）.The rats in captopril group was treated with captopril （100mg·kg-1·d-1 i.g）.After 4weeks,the morphological parameters,histopathology,hemodynamic changes, biochemical analysis were determined in rats.The content of malondialdehyde（MDA）in serum and activities of superoxide dismutase（SOD）,glutathione peroxidase（GSH-Px）in plasma,the content of endothelin （ET）, angiotensinⅡ （AngⅡ）in plasma,myocardial angiotensinⅡ （AngⅡ）were determined.Results Compared with model group,the cardiac coefficient,the left ventricular end diastolic pressure （LVEDP）weredecreasedsignificantly（P0.01）,the mean arterial blood pressure（MAP）and the maximum left ventricular presure rising and dropping rates（±dp/dtmax）were increased significantly in G-Rb3group （P0.01）.In addition,Compared with model group,the contents of MDA in serum,ET,AngⅡin plasma and myocardial AngⅡ were declined （P0.01）,then the activities of SOD and GSH-Px in serum were increased markedly in G-Rb3group （P0.01）. Conclusion G-Rb3has protective effect on ventricular remodeling through inhibitting renin-angiotensin-aldosterone system （RAAS）to reduce contractive material and reinforcing ability of anti-oxidant.