Figure 1.

Cytotoxicity of ouabain. Vero cells were treated with different ouabain concentrations (n = 5). After 120 h of incubation at 37 °C, the CPE score was evaluated using an inverted microscope (A) and the CPE score was obtained (B). After that, the MTT solution (1 mg/mL) was added to each well and then the microplate was incubated for 4 h. The optical density was determined by spectrophotometry at 540 nm (C). MTT values were presented as mean ± standard deviation of three independent experiments. CPE values correspond to the CPE score means for replicates.