Histological analyses in WT and DGKζ-TG mice at 8 weeks after injection of STZ or citrate buffer solution. Hematoxylin-eosin micrographs showing transverse sections of left ventricular myocardium (× 400, bar = 50 μm). Quantitative analysis of cardiomyocyte cross-sectional area (left bar graph) in WT (grey bars) and DGKζ-TG (black bars) mice. Data were calculated by averaging the measurements at least of 100 cardiomyocytes from each sections. Data were obtained from 8 mice for each group.