ERYTHROCYTE REDOX STATE IN UREMIC ANEMIA - EFFECTS OF HEMODIALYSIS AND RELEVANCE OF GLUTATHIONE METABOLISM

Reduced and oxidized glutathione and pyridine coenzymes, glutathione-r elated enzymes and Cu,Zn-superoxide dismutase (Cu,Zn-SOD) were investi gated in the RBC of patients with chronic renal failure (CRF) and in a ge- and sex-matched controls. The effects of hemodialysis (HD) were al so studied. A defective RBC redox state was shown in the CRF group bas ed on a decreased GSH/GSSG ratio and NADPH levels. Increased activitie s of glutathione transferase (GSH-S-T) and Cu,Zn-SOD were observed bef ore HD. Dialysis apparently restores the levels of antioxidant enzymes and at the same time strongly affects the redox state. Thus we can sp eculate that HD can generate severe redox impairment inducing damage i n RBC and plasma antioxidant enzymes. Increased erythrocyte GSSG and G SM-S-T levels coupled with a reduced hexose monophosphate shunt (HMPS) function may be useful indexes of oxidative stress in uremic anemia.