Fig. 1. Cytoxocity and morphology of cells exposed to menadione. (A) Dependence of U937 () and ARPE-19 () cell survival on menadione concentration. 1x10⁴ cells were exposed to menadione (1 µM to 250 µM) for 4 hours and allowed to recover for 24 hours. Cell viability was determined by XTT assay as described in Materials and Methods. Data are represented as mean±s.d. (n=3). (B) Both U937 cells and ARPE-19 cells were exposed to 50 µM menadione for 4 hours and were observed immediately under inverted microscopy. (Inserts) Control ARPE-GFP cells in which GFP is localized to the membrane (left, arrowheads) under similar conditions were observed under confocal fluorescent microscopy and showed the presence of membrane blebs (right, arrows). Images represent three independent experiments. Bar, top, 50 µm; bottom and inserts, 30 µm.

Return to article