Fig. 5.

The inhibitory effect of high glucose on calcium-handling and potassium channel gene expression during GR-E14 cardiogenesis. a mRNA levels of calcium-handling genes, SERCA2A and RYR2. b mRNA levels of potassium channel genes, HCN1 and KCN1. c Representative images of HCN1 immunofluorescent staining (green). DAPI (blue) was for cell nuclei staining. d Quantitative fluorescent density data of HCN1 immunofluorescent staining. e KCN1 protein expression at differentiation day 9. Gene expression was assessed at EB formation day 5 and differentiation day 1, 3, 5, and 7. f Line scan image of fluo 4 in ES cell-derived cardiomyocytes in low or high glucose conditions. g Ca²⁺ wave frequency of ES-derived cardiomyocytes in low or high glucose conditions. Experiments were repeated three times (n = 3). EB embryoid body derived from E14 or GR-E14 cells, HG high glucose (25 mM), LG low glucose (5 mM). Values were dedicated as mean ± SD. ^*Indicates significant difference compared with the other group