(A,B) MPO immunoreactivity on a cross section of the heart showing the transmural ischemic zone (IZ) of the anterior wall of the left ventricle with subepicardial (PIZ-EPI) and peripheral (PIZ-1) peri-infarct zones; (C) MPO- (red) and CD68-immunoreactivity (green) of the peri-infarct zone showing no co-localisation of fluorescence; (D) MPO-immunoreactivity is found in the cytoplasm of polymorphonuclear cells (white arrows); (E) a layer of cellular profiles, immunoreactive for both the MPO and CD68 detected within the subepicardial myocardium; (F) CD68-immunoreactivity is found in the cytoplasm of mononuclear cells (white arrows). Scale bars: A = 0.5 mm, B = 200 μm, C = 75 μm, D,F = 20 μm, E = 50 μm.