Time-course and dose-dependent effects of ox-LDL on HUVSMCs proliferation. During the experiment, medium with 0.4% FBS was employed. At the end of each experiment, a water-soluble tetrazolium salts (WST-1) assay was performed to quantify the number of proliferation cells. (a). Cells incubated with ox-LDL (50 μg/ml) in various periods. * P < 0.05 vs. corresponding 0 h control. NS indicates no significance vs. 24 h incubation of ox-LDL. (b). Cells exposed to various concentrations of ox-LDL, FBS (5%) or Ang II (10-7 M) as indicated. * P < 0.05 vs. corresponding no ox-LDL control. NS indicates no significance vs. ox-LDL (50 μg/ml). Data are mean ± SD of three to six independent experiments determined in duplicate, and expressed as fold increase of absorbance in 440 nm compared with unstimulated cells.