ASIV improves the physiological indexes of STZ-induced diabetic rats and decreases the effects of diabetes on tissue structures. (A) LVEDP and LVSP, (B) ± dp/dtmax and (C) LVW/HW of rats in the different experimental groups. n=10. (D) Hematoxylin and eosin staining in cardiac tissue sections of each group. The black arrow indicates myocardial fibers. (E) Cell survival of H9C2 cells determined by MTT assay. n=8 Data are expressed as the mean ± SD. **P<0.01 vs. the control group. #P<0.05 and ##P<0.01 vs. diabetic group. LVEDP, left ventricular systolic pressure; LVSP, left ventricular end diastolic pressure; ASIV, astragaloside IV; L, low; M, mid; H, high; ± dp/dtmax, maximum left ventricular ascending/descending rate; LVW/HW, ratio of left ventricular weight to heart weight.