TRANSLOCATION OF GLUTATHIONE FROM LYMPHOID-CELLS THAT HAVE MARKEDLY DIFFERENT GAMMA-GLUTAMYL TRANSPEPTIDASE ACTIVITIES

Translocation of intracellular glutathione to the medium was studied in lymphoid cells (grown in tissue culture) that have very high, very low, or intermediate levels of membrane-bond Σc-glutamyl transpeptidase, in the absence and presence of various ihibitors of this enzyme. The data show that glutathione is translocated to the medium by all of the cell lines studied, but that glutathione does not accumulate in he medium unless the cellular transpptidase activity is either very low or substantially inhibited. Translocation of glutathione does not seem to be directly related to the activity of γ-glutamyl transpeptidase. The present and previous findings suggest that translocation of intracellular glutathione is a general property of many mammalian cells. Glutathione exported from cells that have membrane-bound transpeptidase may be recovered by the cell in the form of transpeptidation or degradation products. Translocation of glutathione may also reflect operation of a rather general mechanism that protects and maintains the integrity of cell membranes.