Click on image to view larger version.

Figure 4 Hematoxylin-eosin staining and in situ zymography in atria with RSR and AF. Hematoxylin-eosin staining showed that the cell layer under the epicardium of the atrium was thicker with AF (A) than with RSR (B). In situ zymography showed that the activity of gelatinase, represented as unstained spots from the Biebrich scarlet in the FIZ-GN films, was higher in patients with AF (C) than in those with RSR (D). The activity was completely blocked by an MMP inhibitor, which presented as unstained spots in the FIZ-GN films (E) and which disappeared in the FIZ-GI films (F). Original magnification: x200. Abbreviations as in Figure 1.