Zinc administered on a long-term basis in excess to patients with Wilson s disease blocks in a significant way copper absorption from the gut, prevents its accumulation and toxic action in the organism. The authors investigated the effect of its long-term administration on the plasma concentration of copper, zinc and selenium, on the superoxide dismutase activity in red blood cells and glutathione peroxidase activity in whole blood. In seven patients with Wilson s disease treated with zinc sulphate, 136 mg of elemental zinc for 1.5 years (18 months),the authors assessed the plasma concentration of zinc, copper, selenium and ceruloplasmin, the activity of superoxide dismutase in red blood cells , the activity of glutathione peroxidase in whole blood and the urinary excretion of zinc and copper in 24 hours. Envisaged findings with regard to the diagnosis of the investigated patients and their treatment: elevated plasma zinc concentration and increased urinary excretion, reduced copper and ceruloplasmin plasma concentration and increased urinary copper excretion. The authors recorded also a signi- ficantly elevated selenium plasma cncentration and a significantly higher concentration of supe- roxide dismutase in red blood cells (p < 0.05).The increase of the glutathione peroxidase activity in whole blood in the investigated patients was not significant (p < 0.05). Changes in the values of the investigated parameters in patients with Wilson s disease treated on a long-term basis with zinc indicate the possiblee mutual interaction of zinc with other trace elements with an impact on the activity of the corresponding metalloenzymes, i.e. in the sphere of antioxidant systems.

        Key words: Wilson s disease - Zinc - Copper - Selenium - Superoxide dismutase - Glutathione peroxidase - Treatment.