PARAMETERS OF OXIDATIVE STRESS IN LIVER AND WHITE MUSCLE OF HAKE (Merluccius merluccius L

Fish are the most important organisms in the biomonitoring of aquatic ecosystems. A number of pollutants may cause the oxidative stress in the organism of fish. The monitoring of parameters of oxidative stress in tissues of fish is a good biomarker in the assessment of the condition of environment. Catch of commercially important species of fish, hake (Merluccius merluccius L.) was carried out in front of sea-port Bar (South Adriatic) at the end of May 2005. The parameters of oxidative stress: concentrations of lipid peroxides (LP) and reduced glutathione (GSH) were determined in liver and white muscle. Physical-chemical parameters (salinity, concentration of dissolved oxygen and temperature) as well as the concentrations of nitrites, nitrates and detergents in the water of investigated locality were determined. The obtained results showed the tissue specificity that was the consequence of different metabolic and antioxidative activities. In the liver of hake, the increased concentration of LP was found in comparison to the white muscle, whereas in white muscle the increased concentration of GSH was recorded in comparison to the liver. These results suggest that the intensity of oxidative stress was higher in the liver in comparison to the white muscle, which is the consequence of increased presence of pollutants in water of the investigated locality.