Figure 2.

Age is associated with increased oxidative stress in the lung. Lung homogenate levels of (A) glutathione (GSH) and (B) oxidized glutathione (GSSG) were measured in both young and aged mice exposed to either air (open bars) or cigarette smoke (closed bars) for 1 day. (C) The percentage of glutathione in the oxidized state was calculated and found to be increased at all ages compared with the young mice. Data represented as mean ± SEM with *P < 0.05, **P < 0.01 compared between air and CS; ^§P < 0.05, ^§§P < 0.01, ^§§§P < 0.001 compared with air-exposed young mice; n = 4–6.