Fig. 1.

Cytotoxicity of V (VOSO₄) and its combination with Se (Na₂SeO₃) to CHO-K1 cells as measured with the resazurin assay. The CHO-K1 cells were exposed to 100 μM VOSO₄ in combination with Na₂SeO₃ (0.1, 0.5 or 1 μM) for 48 h and thereafter the cytotoxic effect was assessed with the resazurin test. In this test, the amount of resazurin that was not reduced to resorufin is proportional to the number of injured cells. The absorbance of resazurin in control cells (treated with neither V nor Se) was taken as 100 %. Results are presented as a percentage of control cells and represent mean ± SEM derived from five independent experiments. Differences between means (ANOVA/Dunnett’s T3 test) are indicated by *p < 0.05 significantly lower than control, ^# p < 0.001 significantly higher than control, ^a p < 0.05 significantly higher than V alone