Apoptosis and oxidative stress are aggravated in advanced heart failure. Atrial myocardial sections from the recipient and donor patients were subjected to (A) TUNEL, troponin C and DAPI staining, the number of TUNEL-positive myocytes was expressed as a percentage of total nuclei detected by DAPI staining. and (B) 8-OHdG immunostaining. Representative images of the staining are shown. (C) The ventricular myocardial sections of hearts from old (15 months) and young (3 months) mice were subjected to immunostaining with 8-OHdG, and representative images of the staining are shown.