Long-term oral sildenafil reduced myofibroblast accumulation in the infarction area, but did not significantly counteract the cardiomyocyte loss in this region. (n = 8/group). Paraffin-embedded sections were used. Top: quantitative image analysis of myofibroblasts by immunohistochemistry for ASMA. Middle: representative micrographs for the immunohistochemical detection of troponin T. Bottom: quantitative image analysis of troponin T. UT: untreated control; S: sildenafil; ***p < 0.005.