THE EFFECTS OF SHORT-TERM EXPOSURE TO CADMIUM AND COPPER ON SIALIC ACID IN CARP (CYPRINUS CARPIO) TISSUES

摘要

The aim of the present study was to determine the effects of cadmium and copper on the sialic acid levels of liver, gill, muscle and kidney of Cyprinus carpio following a 7-days exposure period at static conditions. Sialic acids (N-acetylneuraminic acids, SAs) are negatively charged monosaccharides that are common constituents in the oli-gosaccharides of vertebrates and some invertebrate species. Quantitative and qualitative differences in sialic acid are seen in health and disease, and at different stages of cell growth, differentiation, aging and malignant transformation. In this study, adult carps were exposed to 0.5, 2.5 and 5.0 ppm copper and 0.1, 0.5 and 1.0 ppm cadmium, and also for interaction of 0.5+0.1 ppm copper+cadmium concentrations under static conditions for one week. At the end of 7 days, all carps were dissected into their liver, gill, muscle and kidney tissues for evaluation of heavy metal accumulation (Cu and Cd), and for analyzing the sialic acid level. Accumulation of Cu and Cd in the tissues investigated was increased with the dose of the metal. Under in vitro conditions, Cu, which is a useful ion for normal tissue function, has an antagonistic effect with sialic acid in the tissue. In contrast, Cd, which is not involved in any physiological function, has a synergistic effect with sialic acid. According to the results of this study, it could be suggested that tissue sialic acid interacts with metal ions under in vitro conditions. On the other hand, it is also possible that these results are due to direct effects of the metal ions on sialic acid metabolism.