Cooper ions and hypochlorite are mainly responsible for oxidative inactivation of paraoxon-hydrolyzing activity in human high density lipoprotein

Paraoxonase, an antioxidant enzyme, exclusively located on HDL is well known for both hydrolysis of organophosphate and prevention against LDL oxidation. It have been reported that PON1 decrease its activity under oxidative stress and that PON1 activity is lower in subject with higher vulnerability to organophosphate poisoning. The aim of our study is to examine the effect of oxidative system on paraoxon-hydrolzing activity and to elucidate the plausible mechanisms responsible for the decline of HDL-asscociated PON1 activity in vivo system. (omitted)