Figure 4. A: Superoxide production in human lens epithelial cells exposed to dexamethasone. Dexamethasone exposure to human lens epithelial cells for 24 h had no effect on superoxide production. Superoxide production was measured over time and expressed as relative fluorescence units per second and gram protein (RFU s⁻¹g⁻¹). The experiment was repeated twice with similar results. B: Peroxide production in human lens epithelial cells exposed to dexamethasone is also demonstrated. Exposure of human lens epithelial cells to dexamethasone for 24 h resulted in increased peroxide production only at the highest concentration of 100 µM used. The experiment was repeated twice with similar results. Peroxide production is expressed as relative fluorescence units per second and gram protein (RFU s⁻¹g⁻¹). Mean±SEM from three separate culture wells are shown; the asterisk indicates a p<0.05. C: Glutathione in human lens epithelial cells exposed to dexamethasone. Dexamethasone did not affect the GSH level in human lens epithelial cells after incubation with dexamethasone for 24 h. One representative experiment of three is shown. The level of GSH was measured after 2 h and expressed as relative fluorescence units and gram protein (RFU x g-1). Mean ±SEM from 3 separate culture wells is shown.