Myocardial extracellular matrix and cardiac remodeling disruption in young SHS exposure, old and the old SHS exposure rat hearts. (A) Representative images and histological analysis of heart total collagen content using Masson's trichrome staining. Morphological features of cardiac remodeling in young SHS exposure, old and old SHS exposure rat hearts. The left ventricular architecture images were magnified 400x. Resolution with 20μm calibration bar. (B) Quantitative analysis of left ventricular cross-sectional area of collagen content. Densitometric graphs represent means ± SEM. *p<0.05, **p<0.01, significant difference compared to young control. #p<0.05, significant difference compared to old control. (C) Quantitative analysis of left ventricular cross-sectional area of extra-cellular space. Bars represent means ± SEM (N=6). *p<0.05, **p<0.01, significant statistic difference compared to young control. #p<0.05, significant statistic difference compared to old control.