Irreversible inhibition of plasma membrane (Ca2+ + Mg2+)-ATPase and Ca2+ transport by 4-OH-2,3-trans-nonenal.

4-OH-2,3-trans-nonenal (HNE), a major aldehydic lipid peroxidation product, has been shown to cause cellular toxicities and has been linked to a number of pathophysiological processes including atherogenesis. Specifically, in vitro exposure of erythrocyte plasma membrane preparations to HNE resulted in the inhibition of membrane transport function and integrity. To characterize the nature of the inhibitory effects of HNE on plasma membrane regulatory mechanisms, we investigated its effects on substrate and calmodulin (CaM) stimulation on erythrocyte Ca2+ transport and (Ca2+ + Mg2+)-ATPase activities.