The Effect of Cerium on SOD and POD Activities in Hepatopancreas of Oriental Weatherfish(Misgurnus anguillicaudatus)Stressed by Cadmium

The effects of cerium on activities of superoxide dismutase(SOD),and peroxidase(POD)in hepatopancreas of oriental weatherfish(Misgurnus anguillicaudatus)stressed by various cadmium levels.The fish were randomly divided into control group and experimental groups and exposed to solely Ce3+ at a rate of 0.025,0.25 and 2.5mg/L,solely Cd2+ at a rate of 0.025,0.25 and 2.5mg/L,and both Cd2+ and Ce3+ at a rate of 0.025 mg/L Cd2++0.025 Ce3+,0.25 mg/L Cd2++0.25 mg/L Ce3+and 2.5 mg/L Cd2++2.5 mg/L Ce3+.The activities of SOD,and POD were detected in the hepatopancreas at 1,2,3,5,7,and 10 days after the exposure.The SOD and POD activities were found to be significantly(P0.05) or very significantly(P0.01)higher in the low Ce3+ group than that in the control.The higher and lower SOD activities were observed in middle Ce3+ group in the 3d and the 5d,while the higher and lower POD activities appeared in the same group in 5d and in 7 d compared with the control(P0.05 or P0.01).The higher and lower SOD activities were found in high Ce3+ group in 2 d and from 3 d,while the higher and lower POD activities occurred in the same group in 5d and in 7d compared with the control(P0.05 or P0.01).The SOD and POD activities were higher in low Cd2+ group than those in the control(P0.05 or P0.01).The SOD activity in middle Cd2+ group was higher in 7d and lower in 10d,while the POD activity in the same group was higher all the time compared with the control(P0.05).The SOD and POD activities in high Cd2+ groups were higher than those in the control in 2 d.However,the SOD activity was significantly lower in 5 d and the POD activity was lower in 3d compared with the control(P0.05 or P0.01).The SOD and POD activities in low and middle Cd2++Ce3+ groups were significantly higher,but lower in high Cd2++Ce3+ groups compared with the control(P0.05 or P0.01),indicating that low concentration cerium enhanced the activities of SOD and POD,but high concentration cerium inhibited the activities.