Fig. 6. H₂O₂ promoted actin polymerization in astrocytes. The relative intensity of fluorescently labeled F-actin in astrocytes was calculated from the integrated fluorescent intensities per astrocyte normalized to those without H₂O₂ treatment. Each data point represents an average value obtained from at least 150 cells from three independent experiments. Treatment with H₂O₂ (200 µM, 2 hours) increased the polymerization of actin by up to 180% in astrocytes (P<0.01), and pretreatment of cells with SB203580 (20 µM, 30 minutes) suppressed this effect induced by H₂O₂ (P<0.01).