目的 研究参芪扶正注射液足三里穴位注射对心气虚证的效应与用药剂量的关系。方法 通过负重游泳及灌服大剂量心得安法获得心气虚证大鼠模型，对各治疗组分别进行不同剂量参芪扶正注射液的足三里穴注治疗。连续治疗10 d后，观察并记录大鼠的一般状况和症状；通过ELISA法检测各组血清心钠素（ANP）及环磷酸腺苷（cAMP）含量；通过比色法检测各组血清超氧化物歧化酶（SOD）活性；通过HE染色法检测各组心肌组织病理改变。结果 和正常对照组相比，模型对照组出现疲软无力，舌质发紫，呼吸急促等明显的心气虚症状；血清ANP浓度升高，cAMP浓度降低，SOD活性降低，均具有极其显著性意义（P<0.001）； 心肌组织病理示：炎细胞浸润明显，心肌细胞严重水肿，排列紊乱。和模型组相比，各治疗组症状缓解，血清ANP浓度降低，cAMP浓度升高、SOD活性增强，差异均具有显著性意义（P<0.05或P<0.01或P<0.001），其中参芪0.05 mL组变化最小（P<0.05），参芪0.20 mL组变化最大（P<0.001）；心肌组织病理改变减轻，其中参芪0.20 mL组最接近正常。结论 参芪扶正注射液足三里穴位注射能有效治疗心气虚证，且其疗效与用药剂量在一定剂量范围（0.05～0.20）mL内成正相关。
Objective To study the effects of Shenqi-fuzheng injection (SQ) in different doses injected into Zusanli acupoint in treating heart-qi deficiency syndrome and explore its dose-to-effet relationship.Methods The rat model of heart-qi deficiency syndrome was established by forced burden swimming and gavage of large doses of propranlolum. Seven groups of rats were set up with 8 rats in each group: the blank control group, the model group and 5 treatment groups which received a Chinese medicine Shenqi-fuzheng injection (SQ) in different doses (0.05 mL, 0.10 mL, 0.15 mL, 0.20 mL and 0.25 mL per rat, respectively) at ST36 acupoints. The treatment was administered for consecutive 10 days. The general conditions and symptoms of the rats were observed and recorded. The serum concentrations of atrial natriuretic peptide (ANP) and cyclic adenosine monophosphate (cAMP) were assayed by ELISA. The activity of serum superoxide dismutase (SOD) was detected by colorimetry. The pathological changes of myocardial tissue were observed using HE staining. Results Compared with the blank control group, the model group showed obvious heart failure symptoms such as fatigue, purple tongue, short and rapid breath, the concentration of ANP was increased while cAMP decreased, and SOD activity was declined (P<0.001 for all). The pathology of myocardial tissue showed inflammatory cell infiltration and seriously swollen cardiomyocytes in disordered arrangement. Compared with the model group, all treatment groups showed that symptoms were relieved, ANP concentration was decreased, and cAMP concentration and SOD activity were increased. Among them, the changes of indicators in the SQ-0.05 mL group were mildest (P<0.05) while strongest in the SQ-0.20 mL group (P<0.001). The pathological changes of myocardial tissue in the SQ-0.20 mL group were mildest and close to normal. Conclusions ST36 acupoint injection with the Chinese medicine Shenqi-fuzheng injection is an effective therapy for heart-qi deficiency syndrome in rats. The treatment effects are positively correlated with the doses of drug in the range of from 0.05 mL to 0.20 mL per rat.