黄芪对心力衰竭大鼠心功能保护作用

Protective effect and mechanism of Radix astragali on cardiac function of rats with heart failure

目的观察黄芪对腹主动脉缩窄慢性压力超负荷所致心力衰竭大鼠心功能的保护作用及其机制。方法雄性SD大鼠80只,随机选取20只大鼠为假手术组,其余60只制作腹主动脉缩窄模型(CAA),随机分为模型组、黄芪组和阳性对照卡托普利组,每组各20只;各组大鼠在术后24 h开始给药,黄芪组每天腹腔注射黄芪注射液2 mL(2 g/kg),假手术组、模型组和卡托普利组每天腹腔内注射2 mL生理盐水,卡托普利组将卡托普利溶入饮水中(100 mg/kg),连续8周;存活大鼠采用血流动力学测定心功能,计算心指数和左心室指数,免疫组织化学法检测大鼠心肌组织中caspase-3表达。结果与模型组[(2.35±0.298)mg/g]比较,黄芪组和卡托普利组大鼠左心室指数[(1.94±0.186)、(1.98±0.256)mg/g]均明显降低(P<0.01);与模型组比较,左心室收缩压(LVSP)、左心室压力上升/下降最大速率(±dp/dtmax)均升高(P<0.05),而左心室舒张末压(LVEDP)降低(P<0.05);与模型组比较,黄芪组和卡托普利组凋亡蛋白caspase-3表达灰度值[(162.3±10.1)、(173.9±11.6)]均降低(P<0.05)。结论黄芪可能通过减少心肌细胞凋亡,进而改善心力衰竭大鼠的心功能及心肌肥大。

Objective To observe the protective effect and mechanism of Radix astragali on cardiac function of rats with heart failure due to abdominal aorta coarctation.Methods Eighty male Sprague-Dawley（SD） rats weighing 200-220 g were used.Twenty rats were randomly assigned as sham group.The remainder were underwent surgery for abdominal aorta coarctation and randomly divided into the model,Radix astragali and captopril groups,followed by a 8-week treatment with Radix astragali（2 g/kg per day,intraperitoneal injection） or captopril（100 mg/kg per day,drinking water） once a day for 8 weeks.The rats in sham and model group were injected with equal volume of physiological saline.Eight weeks after the treatment,haemodynamic performance of the survivals were measured to assess the cardiac function.The mass of whole heart and left ventricular were determined accurately and the cardiac mass index（CMI） and left ventricular mass index（LVMI） were calculated.Immunohistochemistry procedure was used to detect the expression of caspase-3 in rat cardiac tissues.Results LVMI of Radix astragali and captopril groups were significantly lower than that of model group（P〈0.01）.Cardiac function of Radix astragali and captopril groups were improved.Left ventricular systolic pressure（LVSP）,maximum rate of rise/decrease of LVSP（＋dP/dtmax,-dP/dtmax） were obviously increased（P〈0.05）,while left ventricular end-diastolic pressure（LVEDP） was decreased dramatically than that in the model group（P〈0.05）.The expression of caspase-3 was decreased and gray value was higher significantly in the Radix astragali and captopril groups than that in the model group（P〈0.05）.Conclusion The protective effect of Radix astragali on cardiac function and myocardium hypertrophy of rats with heart failure may result from inhibiting apoptosis of myocardial cells.