Figure 3

Measurement of nitric oxide production and eNOS protein in HUVECs. (A, B) Effects of calpain inhibition on nitric oxide production. HUVECs were incubated with normal glucose (NG, 5 mmol/L) or high glucose (HG, 30 mmol/L) in combination with calpain inhibitor-III (CI-III, 10 μmol/L) or infection with Ad-CAST for 48 h. NO production was measured in culture medium. Data are given as mean ± SD from at least 3 different experiments. ^*P < 0.05 vs. NG treated with vehicle or infected with Ad-gal. ^#P < 0.05 vs. HG treated with vehicle or infected with Ad-gal. (C, D) Effect of high glucose on eNOS. HUVECs were incubated with NG or HG for 48 h. The protein levels of eNOS (C), and eNOS monomer and dimmer were determined (D). (C, D) are representative western blots for eNOS and dimmer formation from 3 different experiments. (E) Nitric oxide (NO) productions. HUVECs were incubated with high glucose in the presence of mitochondria-targeted antioxidant peptide SS31 (5 or 10 μmol/L) or control peptide SS20 (10 μmol/L) for 48 h. NO production was measured in culture medium. Data are given as mean ± SD from 3 different experiments. ^*P < 0.05 vs. SS20.