HDAC1 and 2 levels are elevated in CHF. Left ventricles from sham and infarcted myocardium at three time points: 3 days post MI (AMI), 3 weeks post MI (3w CHF), and 6 weeks post MI (6w CHF) were lysed and separated in 4% to 12% Bis-Tris SDS/PAGE gel and blotted with HDAC1 and HDAC2 antibodies. HDAC1 and 2 levels were normalized with GADPH levels and indicated as arbitrary units in bar graphs for each time points. Western blotting of the infarcted area showed no increase in HDAC1 and HDAC2 levels in AMI (n = 4 for sham, n = 5 for AMI) (A). Significant increases in HDAC1 and HDAC2 levels were detected in the infarcted myocardium compared to sham in 3w CHF (n = 7 for both 3w sham and 3w CHF) (B) and 6 w CHF (n = 4 for 6w sham, n = 6 for 6w CHF) (C). Error bars indicate S.E., P <0.05. CHF, congestive heart failure; HDAC, Histone Deacetylase.