Rainbow trout liver slices: A tool for aquatic toxicology

In this study the feasibility of adapting the precision-cut tissue slice and dynamic organ culture methodology to rainbow trout liver was investigated. The rainbow trout were donated by the U.S. Fish and Wildlife, Service, Alchesay National Fish Hatchery (Whiteriver, AZ) and were kept in a continuous water flow through tank at 10°C. The trout livers were cored and the cores were subsequently precision-cut into slices that had diameters of 8 mm and a thickness of 200 μm. These slices were then placed into dynamic organ culture for 10 d in Waymouth's media plus 10% fetal calf serum at 10°C. Each day the appropriate n umber of slices was taken out of culture and analyzed for viability using the parameters of intracellular K⁺ concentration, alanine aminotransferase (ALT) leakage, and the net accumulation of [³H]leucine into slice protein. Viability of unexposed trout liver slices was maintained for a maximum of 10 d. The cultured trout liver slices were also exposed to 50. 100, and 200 μM cadmiun sulfate, mercuric chloride, and lead acetate. Hepatotoxic responses were seen in this tissue slice system, with cadmium sulfate being the most toxic; followed by mercuric chloride, and lead acetate being the least toxic. This study suggests that precision-cut trout liver slices incubated in dynamic organ culture may become a useful tool for in vitro studies in aquatic toxicology.