Changes in glutathione, glutathione reductase and glutathione-S-transferase as a function of cell concentration and age.

The activities of glutathione-S-transferase (GST) and glutathione reductase (GSR) in mouse lymphocytes as a function of cell concentration and age were determined. Lymphocytes from 2-, 9- and 24-month-old mice were isolated and the activity of GST was determined spectrophotometrically using 1-chloro-2,4-dinitrobenzene as the substrate. Lymphocyte concentrations of 0.44, 0.75 and 0.55 X 10(6) cells/ml were found to be optimal for assaying GST in 2-, 9- and 24-month-old mice, respectively. Determination of GSR activity was based on NADPH reduction of oxidized glutathione and cell concentrations of 0.29, 0.30 and 0.22 X 10(6) cells/ml were chosen for assaying the enzyme activity for the three age groups, respectively. Glutathione levels and GSR activity of mice lymphocytes were higher in 2- and 24-month-old mice as compared to 9-month-old animals. However, GST activity of mouse lymphocytes was low in 2- and 9-month-old mice and increased significantly in 24-month-old animals.