H2S production rate and CSE expressions changes using the d-galactose age-induced cardiomyocytes. a The expression of CSE protein (CSE-C) in primary cultures of neonatal cardiomyocytes. H2S production rate (b) and CSE (CSE-H) expressions (c) in H9C2 cells. 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. control group.