The effects of salinity and salinity+metal (chromium and lead) exposure on ATPase activity in the gill and intestine of tilapia Oreochromis niloticus.

Freshwater organisms are highly sensitive to increases in salinity because they causes serious osmoregulation problems. Salinity of inland waters can be increased as a result of anthropogenic activities. In this study, freshwater fish Oreochromis niloticus were exposed individually to increased salinities (0, 2, and 8 ppt) alone and salinity+metal [1 μg/mL chromium (Cr) or lead (Pb) exposure at 2 and 8 ppt] exposures for different time periods (1, 7, and 14 days) to investigate the response of Na(+)/K(+)-ATPase and Mg(2+)-ATPase in the osmoregulatory tissues (gill and intestine).