Effects of superoxide anions on the (Na + K)ATPase system in rat lung

Oxygen-derived free radicals have been shown to alter endothelial cell functions in lung. Enzymatically generated superoxide anions inactivated (Na + K)ATPase activity and caused lipid peroxidation in lung. Superoxide dismutase or allopurinol, but not ATP, protected this oxy radical-mediated depression of ATPase activity.