Nitrite-induced export of glutathione disulfide from erythrocytes

Export of glutathione disulfide (GSSG) from human erythrocytes induced by several agents (H2O2, t-butyl hydroperoxide, phenazine methosulfate and NaNO2/) was compared. NaNO2 treatment was found optimal for induction of GSSG transport. GSSG was exported from NaNO2-treated erythrocytes mainly via the low-affinity kinetic component. The transport rate increased with increasing pH in the pH range of 6.5-8.0. The transport was inhibited by fluoride, vanadate and intracellular DNP-SG. On the basis of the obtained results, a possibility of existence of one common low-affinity transporter for glutathione S-conjugates and GSSG is discussed.