Figure 4. Pathologic cardiac remodeling in DCM^ANP−/− mice.

A. Representative longitudinal sections of hearts from DCM^ANP+/+ and DCM^ANP−/− mice (12 weeks old). Severe four-chamber dilation was frequently observed in DCM^ANP−/− mice. Scale bars=2 mm. B. Heart weight (HW), body weight (BW) and HW/BW ratio (n= 12–23 in each group). C & D. Representative wheat germ agglutinin (WGA) stain (20×) and quantitation of cardiomycyte cross-sectional area. Results are averages of 100–150 cardiomyocytes from 4–6 mice each group. E & G. Representative Masson’s trichrome stain showing interstitial fibrosis and peri-vascular fibrosis. F & H. Quantitative analysis of interstitial fibrosis (IF, % of total area) and perivascular fibrosis (PF, ratio to lumen area). A total of 12–15 fields (40×) or 12–15 arteries (40×) from left ventricle per heart were measured. Results are means of averages of 3–6 mice for each group. I. Intense perivascular fibrosis involving cardiac veins and various sizes of coronary arteries. C,E,G & I Scale bars=100μm. Dashed lines represent normal reference value from WT mice. ***p<0.001, ^nsp>0.05.