Physiological responses to acute silver exposure in the freshwater crayfish(Cambarus diogenes diogenes)-A model invertebrate?

摘要

Adult crayfish(Cambarus diogenes diogenes) exposed to 8.41±0.17 μg silver/L(19.4/100 as Ag~+) in moderately hard freshwater under flow-through conditions for 96 h exhibited ionoregulatory disturbance, elevated metabolic ammonia(T_amm) pro- duction and substantial silver accumulation in the gills, hemolymph, and hepatopancreas. The ionoregulatory disturbance included both a generally reduced unidirectional Na~+ influx and an increased unidirectional Na~+ efflux, leading to a substantial net loss of Na~+ from the silver-exposed crayfish. The Na~+ uptake in silver-exposed crayfish differed overall from controls, while the increased Na~+ efflux recovered to control values 48 h into the 96 h of exposure.