[Glutathione reductase and glutathione S-aryltransferase in the rat liver depending upon the glutathione level].

After a decrease of protein in rations of rats content of total glutathione was decreased in liver tissue, whereas the glutathione reductase activity was increased in liver cell cytosol. The glutathione reductase activation occurred due to an increase in the enzyme affinity to the substrate. In the rations containing 15%, 10% and 5% of protein the apparent Km values of the glutathione reductase reaction in liver cytosol constituted 91 microM, 74 microM and 50 microM, respectively. The glutathione-S-aryltransferase activity was decreased in liver tissue only under conditions of a distinct protein deficiency.