Antioxidant responses and bioaccumulation in Ictalurus melas under mercury exposure.
Laboratory experiment was carried out to determine mercury accumulation in tissues (gills, kidneys, liver, and muscle) and biochemical responses in the liver of freshwater teleost Ictalurus melas. Catfish were subjected to different concentrations of Hg(2+) (35, 70, and 140 microg/L) for 10 days. The chemical analyses showed higher mercury concentrations for all treatments in gills and kidneys followed by liver and muscle. At the lowest mercury concentration a decrease in glutathione (GSH) content and an increase of GSH peroxidase Se-dependent and glyoxalase II enzymes were observed. An increasing trend was observed also for GSH-S-transferase and glyoxalase I, while GSH peroxidase Se-independent enzyme and GSH reductase showed no significant variation in activities. The increase in the enzymes activities of catfish, involved in the inactivation of reactive molecules formed during oxidative stress, could provide an additional protection against the oxidative damage induced by mercury.
Department of Animal Biology and Ecology, University of Perugia, Via Elce di Sotto, I-06123 Perugia, Italy. elia@unipg.it
Antonia Concetta
AC
Elia
Roberta
R
Galarini
Maria Illuminata
MI
Taticchi
Ambrosius Josef Martin
AJ
Dörr
Luciana
L
Mantilacci
D000818:Animals; D000975:Antioxidants / Q000378:metabolism*; D005978:Glutathione / Q000378:metabolism; D005979:Glutathione Peroxidase / Q000378:metabolism; D005980:Glutathione Reductase / Q000378:metabolism; D005982:Glutathione Transferase / Q000378:metabolism; D007059:Ictaluridae / Q000378:metabolism*; D008628:Mercury / Q000378:metabolism* / Q000493:pharmacokinetics / Q000633:toxicity*; D014018:Tissue Distribution
D000975:Antioxidants; D005979:Glutathione Peroxidase; D005980:Glutathione Reductase; D005982:Glutathione Transferase; D008628:Mercury; D005978:Glutathione