VANADIUM AND OXYGEN FREE-RADICALS - INHIBITION OF SUPEROXIDE-DISMUTASE AND ENHANCEMENT OF HYDROXYDOPAMINE OXIDATION

1) The effect of vanadium on superoxide dismutase activity (SOD), as well as on the rate of hydroxydopamine oxidation was studied in vitro since lipid peroxidation has been implicated in cell damage by vanadium. 2) Vanadium strongly inhibits SOD activity, the degree of inhibition increasing with time. 3) Vanadium enhances the rate of hydroxydopamine autoxidation. Maximal oxidation in the presence of 1-mu-g/ml vanadium was 3 minutes in comparison to 8 minutes in control system. 4) The combination of excessive oxygen free radical production and inhibition of their elimination by inhibition of SOD activity, may contribute to vanadium toxicity and carcinogenicity, in which lipid peroxidation has been already implicated as the mechanism of cell damage.