Abstract

In present work, some biochemical characteristics of the catfish, Clarias gariepinus were studied under the effect of different sublethal doses of 4-nonylphenol (0, 0.05, 0.08 and 0.1 mgl^-1). Liver enzymes ALT and AST increased insignificantly at P<0.05 whereas the ALP decreased insignificantly. The activities of G6PDH showed significant increase with the increased sublethel doses of 4-nonylphenol while the activities of LDH decreased insignificantly with increase of such doses. The concentrations of serum glucose and total cholesterol significantly increased after exposure to 4-nonylphenol, although Hyperglycemia is evident. The kidney function parameters such as total serum protein and uric acid increased insignificantly after exposure to 4-nonylphenol in comparison with the control fish whereas creatinine exhibited significant increase (P<0.05). Some serum ions decreased significantly (HCO₃^- and Na⁺) or insignificantly (Cu⁺², Cl^-and Ca⁺²) and others increased significantly (Fe⁺²) or insignificantly (K⁺) under 4-nonylphenol stress on C. gariepinus. Increased serum anion gap was associated with increased hyperglycemia and insignificant hypocalcemia. Such increased gap referred to nonylphenol-induced metabolic acidosis. The adverse impact of the sublethal doses of 4-nonylphenol on the molecular structure of the protein was evident by electrophoresis. In conclusion, in addition to its tissue-specific estrogenic effects, 4-nonylphenol has non-estrogenic adverse effects on liver and kidney functions through activation of other metabolism-related genes distinct from estrogen-responsive genes.

Key words: Biochemistry, liver, kidney, anion gap, 4-Nonylphenol.