Detection of ROS generation and cell apoptosis in cardiac tissue in different groups. (a) Intracellular ROS generation detection in vivo by DHE staining. The left side shows fluorescence microscopic images of cardiac frozen sections in Ctrl, NAC, DCM and DCM + NAC. The right side demonstrates the values of fluorescence intensity which stand for level of ROS generation. (b) Determination of in situ apoptosis in cardiac tissue in Ctrl, NAC, DCM and DCM + NAC groups. The left side represents TUNEL assay of paraffin- embedded myocardial tissue slides in Ctrl, NAC, DCM and DCM + NAC groups. Representative photomicrographs of TUNEL staining in myocytes are indicated by black arrows. The right side shows the qualification of TUNEL- positive (yellow- brown stained) cardiomyocytes. Columns in this figure indicate detected values of Ctrl, NAC, DCM and DCM + NAC respectively in (mean ± SD) manner. a Values are significantly different from Ctrl; b values are significantly different from NAC; c values are significantly different from DCM. [(&)P < 0.05; (#)P < 0.01; (*)P < 0.001].