The objective of this study was to investigate the mechanism of Huangqi（Astragali Radix）-Tinglizi（Descurainiae Semen）improving cardiac function in rats with heart failure by modulating AMP-activated protein kinase（AMPK）/mammalian target of rapamycin（mTOR）pathway and influencing autophagy.

Sixty male SD rats of SPF grade were selected，with 8 randomly assigned to the control group（CON）. The remaining rats received subcutaneous injections of isoproterenol solution at a dose of 3 mg·kg^-1 on the back of their shoulders for 10 consecutive days to induce heart failure. Forty heart failure rats were randomly allocated into five groups：model control group（MC），Huangqi（Astragali Radix）-Tinglizi（Descurainiae Semen）low-dose group（HTL），Huangqi（Astragali Radix）-Tinglizi（Descurainiae Semen）medium-dose group（HTM），Huangqi（Astragali Radix）-Tinglizi（Descurainiae Semen）high-dose group（HTH），enalapril group（ENA）. Each group consisted of eight rats. Following a 14-day period of drug administration，B-ultrasound was used to measure the left ventricular ejection fraction（LVEF）and left ventricular short axis shortening rate（LVFS）. The left ventricle was then isolated and weighed，and the length of the tibia was measured. The levels of type B natriuretic peptide（BNP）and atrial natriuretic peptide（ANP）in serum of rats were determined by enzyme-linked immunosorbent assay（ELISA）. Histopathological changes in the myocardium were observed using Hematoxylin-eosin（HE）and Masson staining. Western blot analysis was employed to assess the activation status of autophagy-associated protein sequestosome 1（SQSTM1/p62），microtubule associated protein 1 light chain 3（LC3）and AMPK/mTORpathway proteins.

The results of the study indicated that in MCgroup，there was a significant decrease in LVEF and LVFScompared to those in CON group（P<0.01）. Additionally，the heart index，left ventricular mass index and heart to shin ratio were found to be significantly increased in MCgroup（P<0.01，P<0.01，P<0.05）. Furthermore，the serum levels of BNPand ANPwere significantly increased（P<0.01）. MCgroup also exhibited aggravated myocardial tissue pathological injury and fibrosis as well as increased expressions of p-AMPK/AMPK and LC3-Ⅱ/LC3-I（P<0.01）. Conversely，the expressions of p-mTOR/mTOR and p62 were decreased（P<0.01）. In comparison to MC group，the HTH group and ENA group exhibited significant increases in LVEF and LVFS（P<0.01）. Additionally，there were significant decreases in heart index and heart-tibial ratio（P<0.01，P<0.05）as well as significant decreases in serum levels of ANP and BNP（P<0.01，P<0.05）. Moreover，the degree of myocardial tissue pathological injury and fibrosis was alleviated. The expressions of p-AMPK/AMPK and LC3-Ⅱ/LC3-I were decreased（P<0.01），while the expressions of p-mTOR/mTOR and p62 were increased（P<0.01，P<0.05）.

By modulating the AMPK/mTOR signaling pathway，Huangqi（Astragali Radix）-Tinglizi（Descurainiae Semen）is able to attenuate the hyperactive autophagic flux in rats with heart failure and ameliorate their cardiac function.