RED-BLOOD-CELL PERMEABILITY TO THIOL COMPOUNDS FOLLOWING OXIDATIVE STRESS

The permeability of red blood cells (RBCs) to thiol containing compoun ds, reduced glutathione (GSH) and N-acetyl cysteine (NAC), has been st udied in control adult and neonatal cells and after oxidative stress. NAC penetrates the cell. membrane easily while GSH hardly permeates. W e measured their capacity to enhance intracellular non-protein thiols (NPSH), after inducing damage to the membrane by formation of defects. Diamide, phenazine methosulfate (PMS) and t-butyl hydroperoxide (BHP) were chosen as exogenous oxidants, each inducing damage by a differen t mechanism. Our data indicate that although neonatal cells are more s ensitive to oxidative stress, only membrane damage induced by diamide, renders adult and neonatal cells permeable to GSH. NAC treatment enha nces thiol levels in cells exposed to oxidizing agents, as well as in control cells.