Ox-LDL and Ang II induced ROS generation in HUVSMCs and effects of three CCBs (lacidipine, amlodipine and ( S- )-amlodipine) and NAC. Cells were pretreated for 30 min with or without CCBs or with NAC (5 mM), and then treated with Ang II (10-7 M) or ox-LDL (50 μg/ml) for 1.5 h. Then, the DCFH-DA (10 μM) probe was added and incubated away from light for another 30 min. Thereafter, cells were immediately washed twice with PBS, and added to 400 μL DMEM, and the fluorescent intensity was read five times and averaged. The excitation wavelength is 504 nm, and the emission wavelength is 529 nm. Data are mean ± SD of five to eight independent experiments determined in duplicate (three independent experiments for (S-)-amlodipine), and expressed as fold increase of DCF fluorescence intensities compared with unstimulated cells. * P < 0.05 vs. corresponding no ox-LDL control. # P < 0.05 vs. ox-LDL. NS indicates no significance vs. ox-LDL.