HDAC1 is co-localized with cardiac fibroblast in the infarcted and non-infarcted myocardium in CHF. Coronal (LA) and axial (LV, RV) sections of sham and 6w CHF hearts were stained for HDAC1 (A-G) and fibroblast marker CD90. DAPI (Blue) is used to stain nuclei. CD90 and HDAC1 staining were co-localized in remote LV, RV, and LA and infarcted myocardium. White arrows indicate co-localization of CD90+ cells with HDAC1. Scale bars: 100 μm. CHF, congestive heart failure; LA, left atrium; HDAC, Histone Deacetylase; LV, left ventricle; RV, right ventricle.