Sensitivity of erythrocytes to oxidant stress in uremia.

The erythrocytes from 19 chronic hemodialysis patients were examined for Heinz bodies and their sensitivity to oxidant stress. Heinz bodies were found in 63% of patients and an elevated level of oxidized hemoglobin in 36%. When exposed to acetylphenhydrazine oxidant stress, 84% had a normal response and 95% had stable reduced glutathione levels. Ascorbic-acid-induced oxidant stress was tolerated by 84%. The activities of enzymes associated with the hexose monophosphate shunt were examined and found to be intact. This study demonstrates an increased number of Heinz bodies in hemodialysis patients. However, this is not due to an increased sensitivity to oxidant stress. Other mechanisms must be sought to explain the presence of Heinz bodies in these patients.