To further confirm whether the drug had an inhibitory effect on myocardial fibrosis, we extracted left ventricular tissue proteins to detect the expression of myocardial fibrosis‐related proteins using western blot (Figure 4E–I), and compared with the Chow + 0.9% NaCl group, PCNA (a protein involved in the process of cell proliferation and DNA synthesis) and fibrosis markers in the HFpEF + 0.9% NaCl group (including Col1, TGF‐β1 and ɑ‐SMA) were elevated to different degrees. Here, PCNA is linked to Myocardial fibrosis.