MPO and myocardial infarction: The abundance of MPO immunoreactivity was greater in the peri‐infarct and infarct regions, relative to both sham hearts and the non‐infarcted myocardium of infarcted hearts; however, MPO immunoreactivity did not differ significantly between MK2+/+ and MK2−/− mice 3‐ or 5‐days post‐MI.