(a, b): General histopathology as assessed by H&E (upper) reveals cardiac lesion. Further characterization by Masson’s trichrome (middle) staining shows interstitial fibrosis, which is more severe towards the subendocardium. (c) TUNEL staining for apoptosis analysis of myocardial tissue sections. TUNEL positive nuclei are stained with FITC (green; arrows). Cardiomyocytes were identified by αactinin immunostaining (red). Nuclei were stained with DAPI (blue). Percentages of TUNEL positive nuclei were 0.40%, 0.26%, 0.12%, and 0.03% for endo, mid, epi, and control endo, respectively. H&E: hematoxylin and eosin, FITC: fluorescein isothiocyanate, DAPI: 4'-6'-diamidino-2-phenylindole.
