Acta Biologica Tomus XXXVIII. Fasciculi 1-4. [antikvár]

Acta BroL. Szeged. 38. pp. 3-9 (1992) METALS EFFECT ON nSH TISSUES L EFFECTS OF CHRONIC MERCURY AND SELENIUM TREATMENT ON YOUNG TILAPIA TISSUE ENZYMES AND LIPID PEROXIDATION Amal a. Radyi, Nadia Saber^, H. M. Kotkat^, B. Matkovics", and A. M. nour5 'Department of Biochemistry Faculty Veterinary Medicine, Alexandria University, Alexandria, Egypt. ^National Institute of Oceanography and Fisheries, Anfoushy, Alexandria, Egypt. ^Biological Research Center, Hungarian Academy of Sciences, Biochemistry Institute, Szeged, Hungary. ^Biological Isotope Laboratory, "A. J." University, H—6701 Szeged, P. O. B. 539. Hungary. (Correspondence and reprint request) ^Department of Animal Production, Faculty of Agriculture, Alexandria University, Alexandria, Egypt. (Received: May 12, 1992) Abstract Chronic treatment was conducted with different concentrations of mercury chloride (HgClj) and sodium selenite (NajSeOj) alone and an in combination. Effect of chronic treatment was studied on some metallo-enzyme and lipid peroxidation of liver and muscle tissues. Both metals showed a strong concentration-dependent toxic effect on enzyme activities. Key words: Mercury chloride and sodium selenite intoxication, tilapia hybrid, enzymes activity changes, lipid peroxidation. Introduction Numerous studies deal with the characteristic effect of Hg2+ and Se on vertebrates. In earlier works where the effect of CUSO4 respectively, were studied in fishes it was demonstrated that the compounds are affected by the formation of "oxidative stress" in fish tissues. Upon treatment with ZnS04 oxidative stress similar but slighter is induced (Rady et al., 1988). It was demonstrated that Hg2+ salts induce oxidative damage (state of oxidative stress) first of all in the kidney tissues of rat by dismutating superoxide (Oj-) anion which resulted in H2O2 formation. Thereby accumulation of HjOj is the cause of oxidative damage. Oxidative