Effects of acetaminophen on methemoglobin, superoxide dismutase and Na(+)-K+ ATPase activities of human erythrocytes.

It is established that acetaminophen exhibits oxidative behaviour. The effects of acetaminophen (0.3-14.5 microM) on methemoglobin levels, superoxide dismutase and Na(+)-K+ ATPase activities of normal and vitamin E or vitamin C pretreated erythrocytes were investigated. In acetaminophen incubated erythrocytes, methemoglobin concentration and superoxide dismutase activity were increased in a dose and incubation-time dependent manner, the activity of Na(+)-K+ ATPase was decreased by acetaminophen treatment. Vitamin E (1mg/dl of erythrocyte suspension) or vitamin C (1mg/dl of erythrocyte suspension) provided partial protection of hemoglobin, superoxide dismutase and Na(+)-K+ ATPase against acetaminophen action. Vitamin E was more effective than vitamin C.