Impact of the level of SRF overexpression on cardiac fibrosis development.

<p>(A) Western blot analysis of vimentin protein. (B) Quantification of vimentin protein level (n = 4). Data are presented as means ± s.e.m. ** indicates significant difference at P < 0.01, respectively versus the control group. (C) Vizualisation of cardiac fibroblasts by vimentin staining of heart sections from control, SRF-LL and SRF-HL mice. Longitudinal frozen section showing the localization of cardiac fibroblasts stained with vimentin (red) and polymerized actin in myocytes labeled with Alexa-Fluor-488-phalloidin (green). These data are representative of three independent experiments. Scale bar: 80 μm. (D) Confocal microscopic view of Ki67 labeling (pink), nuclei (blue) and vinculin (green). Ki67 labeling is stronger in the SRF-HL than the SRF-LL and control mice and is exclusively located in the interstitial cells. The enlargement is of twice. These data are representative of three independent experiments. Scale bar: 80 μm. (E) Confocal microscopic view of Ki67 labeling (pink), vimentin (green) and nuclei (blue) of heart sections from SRF-HL and control mice. Top panel, scale bar: 100 μm; bottom panel corresponding to the square indicated in the top panel, scale bar: 10 μm. These data are representative of two independent experiments.