EFFECTS OF AN ORGANOPHOSPHATE ON THE ANTIOXIDANT SYSTEMS OF FISH-TISSUES

The effect of a Hungarian made and applied insecticide, organophosphat e (Dichlorvos) on antioxidant enzymes and other oxidative and redox pa rameters of true different fish species, carp (Cyprinus carpio L.) and catfish (Ictalurus nebulosus) was studied. The two fish species have different ways of life. From antioxidant enzymes, changes in superoxid e dismutase, catalase, glutathione peroxidase and, in the case of carp , acetylcholinesterase activities were studied in tissue homogenates. Other parameters studied: changes of lipid peroxidation, reduced gluta thion and two radicals, which are superoxide and hydroxyl radicals. Ou r results showed that the organophosphate tested, besides its inhibito ry effect on acetylcholinesterase - or together with it - induces chan ges characteristic of ''oxidative stress''.