Interaction of glutathione and ascorbic acid in guinea pig lungs exposed to nitrogen dioxide

The interaction of two important water-soluble antioxidants, glutathione and ascorbic acid, was studied. The perfused guinea pig lung was found to contain about twice as much reduced glutathione as ascorbic acid. Nitrogen dioxide exposure decreased the levels of the two antioxidants both in vitro and in vivo. Ascorbic acid concentration was lowered to a greater extent than glutathione. The pulmonary ascorbic acid level was identical in both control and glutathione-deficient guinea pigs exposed to nitrogen dioxide, suggesting that there was little interaction between the two antioxidants in the lungs during oxidant stress.