Effect of oxygen free radicals on rabbit and human erythrocytes. Studies on cellular deformability

Changes in deformability of rabbit and human erythrocytes caused by exposure in vitro to the oxygen free radical generator hypoxanthine and xanthine oxidase were studied. The deformability reduction observed after 30 min of exposure to hypoxanthine-xanthine oxidase could be prevented by pretreatment with SOD, while after only 5 min of such exposure allopurinol and catalase also appeared to have a protective effect. Exposure of human erythrocytes to hypoxanthine and xanthine oxidase in Krebs solution prevented an otherwise occurring hemolysis. Exposure to both substances or to xanthine oxidase alone in Dulbeccos phosphate solution produced a reduction in deformability. The results indicate that exposure of erythrocytes to free oxygen radicals reduces deformability and that this effect may contribute to the myocardial dysfunction and the epicardial erythrostasis observed during open-heart surgery.