Energy turnover and free radical metabolism of erythrocytes

The erythrocyte is a highly specialized cell serving especially for the tra nsports of oxygen and carbon dioxide. For energy production the mature eryt hrocyte is dependent on glycolysis with predominantly glucose as substrate. In the glycolysis and oxidative pentose phosphate pathway NADH and NADPH a re generated; these compounds are used for the reduction of methemoglobin a nd of the antioxidant glutathione, which is highly concentrated within the erythrocytes. In general, the erythrocytes possess avery effective antioxid ative protective system. In comparison to other cell types the erythrocytes show high activities of antioxidative enzymes. Furthermore, the erythrocyt es contain the dominant share of non-enzymatic antioxidative capacity of th e whole blood, too. The circulating erythrocytes can be called as mobile fr ee radical scavengers which are able to protect other tissues and organs. I n patients with chronic renal failure an imbalance between prooxidative rea ctions and antioxidative protection has been described. That oxidative stre ss is strengthened by the hemodialysis with its prooxidative factors and an tioxidative protection-reducing conditions. The renal anemia contributes to the increase of the oxidative stress in chronic renal failure. In relation to free radical metabolism there are no arguments against, but only for a complete correction of renal anemia.