Figure 4: Comparison of histological images 4 weeks after surgery for an MI rat ((a), (b)) and a sham rat ((c), (d)). (a) Myocardial tissue slice of MI rat-blue stain corresponds to the infarcted area in the anterior and lateral regions of the heart. Significant wall thinning is evident in infarcted areas. (b) Hematoxylin-eosin-stained slice from an infarcted rat × 10 magnification (scale bar = 100 μm). Loss of myocytes is evident in the infarcted area which is rich with atypical nuclei. (c) Myocardial tissue slice of a sham rat. Absence of blue stain confirms that LAD ligation caused myocardial infarction in infarcted rats. (d) Hematoxylin-eosin-stained slice from a sham rat × 10 magnification (scale bar = 100 μm). Appropriate alignment and no loss of myocytes indicate absence of infarction.