Is Na,K-ATPase the target of oxidative stress?

Abstract

The susceptibility of Na,K-ATPase from bovine brain to various compounds containing active oxygen radicals is assessed. Sodium nitroprusside slightly inhibits Na,K-ATPase, while light-induced NO" radicals (controlled by the rate of ascorbate oxidation) have no effect on the enzyme. When added in concentrations equally effective in the ascorbate oxidation assay, hydrogen peroxide and sodium hypochlorite inhibit Na,K-ATPase by 70 and 25-30%, respectively. The Fe-dinitrosyl-cysteine complex is the most potent (Ko5=20 pM) inhibitor of Na,K-ATPase. It is demonstrated that different free oxygen radicals accumulated in the ischemic brain cause different kinds of damage to Na,K-ATPase.

The influence of iron ions on ATP-hydrolases activity of cell membranes of rat colon smooth muscle and kidney

“…Известно, что Na + ,K + -AТРаза рассматривается как потен-циальная мишень оксидативного стресса [15]. Функциональные нарушения Na + ,K + -AТРазы происходят при развитии ряда патологий по-чечного эпителия, в том числе при ишемии, со-провождаясь снижением ее активности [16,17].…”