. "We observed a change in the cytosolic FRET image of the C probe from green (reducing) to blue (oxidizing) in response to the treatment of both types of cell with either oxidative agents such as H2O2 or nonoxidative reagents, such as 3-amino-1,2,4-aminotriazole (ATZ), an inhibitor of catalase, or buthionine sulfoximine (BSO), an inhibitor of glutathione synthesis (Fig. 3A and B; also see" . . .