EFFECT OF CHANGE IN ENVIRONMENTAL-TEMPERATURE ON ANTIOXIDANT ENZYME-ACTIVITIES AND LIPID-PEROXIDATION IN RED-BLOOD-CELLS OF CARP

1. Carp (Cyprinus carpio L.) were cultivated in a thermostated aquarium following insertion of cannulae into the dorsal aortas. The water temperature in the aquarium was gradually increased (in a range of 4-22-degrees-C) and blood samples were taken at every 6-degrees-C. The red blood cells' (RBC's) antioxidant enzyme activities and lipid peroxidation were measured at the given temperature. 2. Lipid peroxidation decreased with the gradual increase in temperature, while it increased with temperature decrease. There are opposite changes in the reduced glutathione content of red blood cells. 3. From the RBCs antioxidant enzymes measured, activities total superoxide dismutase enzyme (t-SOD) increased step-by-step with the gradual increase in water temperature, but there was a more marked decrease on lowering the temperature. 4. Glutathione peroxidase activity changed similarly to t-SOD activities, the difference being that GP-ase activities showed slower tendency during decrease than during increase of temperature. 5. A change in the total protein content also followed.