Response of neonatal rat cardiomyocytes to 10 g/L d-galactose for 48 h. a The number of SA β-gal-positive cardiomyocytes. Phase-contrast images showing morphologic changes and stained cells. (SA-β-gal positive cells; Blue, magnification ×400). The aging cardiomyocytes in at least five random fields were counted. b H9C2 cells division index. Five fields (at least 100 cells of each field) were randomly selected and the percentage of cell division was calculated. c The expression of p21Cip/WAF-1 and cyclin D1. The intensity of each band was quantified by densitometry, and data were normalized to the GAPDH signal. All data were from four independent experiments. *p < 0.05 vs. 0 g/L d-galactose for 48 h group.