枸杞多糖对异丙肾上腺素致心力衰竭大鼠的保护作用及其机制

Cardioprotective Effect of Lycium Barbarum Polysaccharides on Isoproterenol-induced Heart Failure in Rats and Its Mechanism

目的探讨枸杞多糖对异丙肾上腺素致心力衰竭大鼠的保护作用及其机制。方法 SD大鼠皮下注射异丙肾上腺素5mg.kg-1.d-1,连续给药7d,建立心力衰竭模型,观察枸杞多糖灌胃给予大鼠30d,对心力衰竭大鼠心功能、心肌损伤标志酶和抗氧化酶的影响。结果枸杞多糖(50、100和200mg.kg-1)可降低心力衰竭大鼠血清心肌损伤标志酶心肌肌钙蛋白(cTn-I),改善心率;升高收缩压、左心室收缩压(LVSP)和左心室内压最大上升速率(+LVdP/dtmax),改善左心室收缩功能;升高左心室内压最大下降速率(!LVdP/dtmax),改善左心室舒张功能;提高血清和心肌超氧化物歧化酶(SOD)水平,并相应降低脂质过氧化物丙二醛(MDA)的含量。结论枸杞多糖对心力衰竭大鼠具有保护作用,其机制与其提高机体抗氧化酶的作用有关。

Objective To explore cardioprotective effect of lycium barbarum polysaccharides on isoproterenol-induced heart failure in rats and its mechanism.Methods Heart failure was induced by subcutaneous injection of isopreterenol 5mg·kg-1 once daily for 7 consecutive days in rats.Lycium barbarum polysaccharides was orally administered for 30 days.Cardiac function,level of myocardial injury marker enzyme and lipid peroxidatase,and activities of antioxidative enzymes in serum and myocardium were measured.Results Administration of lycium barbarum polysaccharides（50,100,and 200mg·kg-1,respectively） significantly decreased the level of myocardical injury marker enzyme of cardiac troponin I（cTn-I）,significantly improved heart rate,systolic blood pressure and left ventricular functions including contractile function（increased LVSP and ＋LV dP/dtmax） and diastolic function（increased-LV dP/dtmax）,significantly increased the activities of superoxide dismutase（SOD）,and significantly decreased the content of lipid peroxidation product of malondialdehyde（MDA） in serum and heart tissues of heart failure in rats.Conclusion Our results suggest that lycium barbarum polysaccharides has a significant cardioprotection against isoproterenol-induced heart failure through enhancing the activities of antioxidative enzymes.