Figure 9
mH2O2 is required for developmental cardiomyocyte number expansion during preadolescence. (A) mH2O2 scavenging, using transgenic expression of catalase to mitochondria (m-CAT-Tg mice), reduced the number of ventricular cardiomyocytes in preadolescent P16 mice compared to WT littermate controls. **P < 0.01. Error bars indicate SEM. (B) A phase-contrast image of cardiomyocytes from a WT P16 disaggregated heart in a hemocytometer field. The image shows that cardiomyocytes can be readily identified because of their size and rod shape.
