Effects of buthionine sulfoximine (BSO) on GSH concentration, ROS production, cell survival, and expression of drug transporters. J45.01 cells were incubated with BSO for 48 hrs and the level of cellular GSH (A), cell survival (C), and changes in the expression of drug transporters (D) were determined. Early changes in the level of ROS were determined in J45.01 cells exposed to BSO for 24 hrs (B). The results are averages±SD (A, B, C) or a representative (D) of three independent experiments.