Responses of the Antioxidant and Osmoregulation Systems of Fish Erythrocyte Following Copper Exposures in Differing Calcium Levels

• Published in: Bulletin of environmental contamination and toxicology Vol. 97; no. 5; pp. 601 - 608
• Main Authors: Canli, E. G., Atli, G., Canli, M.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.11.2016; Springer Nature B.V
• Subjects: Animals; Antioxidants; Antioxidants - metabolism; Aquatic Pollution; Calcium; Calcium - metabolism; Calcium - pharmacology; Cichlids - blood; Copper; Copper - toxicity; Dose-Response Relationship, Drug; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Enzymatic activity; Erythrocytes; Erythrocytes - drug effects; Erythrocytes - metabolism; Exposure; Fish; Fresh Water - chemistry; Freshwater fish; Oreochromis niloticus; Osmoregulation; Osmoregulation - drug effects; Pollution; Soil Science & Conservation; Waste Water Technology; Water Management; Water Pollutants, Chemical - toxicity; Water Pollution Control; Osmoregulation; Freshwater fish; Calcium; Copper; Antioxidant
• ISSN: 0007-4861; 1432-0800
• DOI: 10.1007/s00128-016-1931-3

Freshwater fish Oreochromis niloticus were exposed to Cu in differing Ca 2+ levels (15, 30 and 90 mg/L), using acute (0.3 µM, 3 d) and chronic (0.03 µM, 30 d) exposure protocols and enzyme activities related to the antioxidant (catalase, CAT, EC 1.11.1.6; superoxide dismutase, SOD, EC 1.15.1.1; glutathione peroxidase, GPx, EC 1.11.1.9) and osmoregulation (Total, Na + /K + -ATPase, EC 3.6.3.9, Mg 2+ -ATPase, EC 3.6.3.2) systems in the erythrocytes were measured. Activities of antioxidant enzymes generally decreased significantly following either Ca 2+ alone or Ca 2+ +Cu combinations in both acute and chronic exposures. Na + /K + -ATPase activity significantly decreased in chronic exposures, though there was no clear trend in acute exposures. Mg 2+ -ATPase activity increased significantly in acute exposures, but not in chronic ones. There were more significant alterations in acute exposure compared to chronic ones. There was no clear trend regarding Cu toxicity and its relationship with Ca 2+ , which may possibly be prompted by the compensatory mechanisms of the enzymes. It may be concluded that freshwater fish erythrocytes may face different degrees of more physiological stress from different waters.