After 5/6 Nx, the myocardial structure of mice was disordered, and cardiac fibrosis was obvious compared to that in WT mice; however, these aberrant changes in cardiac tissues were abolished in CCN1−/− mice or CCN1−/− + CKD mice (Figures 4(b), 4(c), and 4(d)). This evidence concerns the gene CCN1 and fibrosis.