Behavioral And Biochemical Responses In Freshwater Fish Carassius Auratus Exposed To Antiepileptic Drug Carbamazepine

Recently, the effects of pharmaceuticals to living organs were studied widely as analytical detection techniques are improving and awareness of the treats drugs pose to the aquatic environment and human health. Researchers have studied the effects of carbamazepine on behavior and biochemical parameters, however, few researchers has considered if the effects were reversible and the bio-concentration of this drug. In this study, the behavioral and biochemical effects and its recovery of carbamazepine in different concentrations were investigated and the concentrations of exposed and recovery stage in different tissues were measured.After exposure to low concentrations 6.15 μg/L and 61.5 μg/L, the time to capture the 1st and 5th prey had no difference with control group, while after the exposure of higher concentrations 615 μg/L and 6150 μg/L, the time to capture the 1st and 5th prey increased significantly. However, when consuming the 10th prey, the time spent was significant lower than that of control group in all the concentrations except 61.5 μg/L. The total numbers of prey consumed in low concentrations 6.15 μg/L and 61.5 μg/L had no difference with control group, while in higher concentrations 615 μg/L and 6150 μg/L this parameter were significant lower than control group. The total transitions to the opposite half were significant inhibited in higher concentrations 615 μg/L and 6150 μg/L, while in 6.15 μg/L and 61.5 μg/L no difference was found. The time spent in the opposite half increased with the exposed concentration, however, no significant difference was found with control group. The average swimmning speed, average acceleration, swimming distance and active duration were significantly reduced compared with the contral group after exposure to all concentrations for 7 days, and these parameters decreased with the increasing concentration. While in the 7 days of recovery period, these indicators only recovered to normal in 6.15 μg/L.In the exposed stage, all the condition status parameters had no significant difference with control group except the liver weight and hepatosomatic index which had a significant increasing trend. The hepatosomatic index was higher than control group and low concentration group in 615μg/L and 6150μg/L, and got to the maximum at 615 μg/L in exposed stage. This value is significant higher than control group, and then it recovered to the level of control group. Besides, apart from the blank control group, the hepatosomatic index of recovery stage was lower than that of exposed stage. The activity of AChE in brain was induced by all concentrations except 6.15 μg/L. In 61.5 μg/L the activity of AChE had obvious increasing trend with time, while the trend with increasing concentration were not significant. In recovery stage, the activity of AChE came back to the level of control group. The activity of SOD in liver and gill were significant induced by carbamazepine, and in recovery stage they would back to normal. While the activity of CAT in liver and gill were significant inhibited by carbamazepine, and in recovery stage only the fish exposed to lower concentrations like 6.15 μg/L and 61.5 μg/L would back to normal.Carbamazepine was accumulated in brain, liver and gill along the time and exposed concentration, at the 7th day, the concentration came to the maximum. The concentration of brain and liver was significantly larger than that in gill. In recovery stage, the concentration of carbamazepine in different tissues was decreased along the time, in the 7 day, the concentration came to its minimum. However, the residual concentration in different exposed group was nearly the same. The bio-concentration factor (BCF) values varied among tissues, the values were 1.10-148.55 in brain, 1.48-181.79 in liver,0.63-97.67 in gill during the whole exposed stage. The BCF were maximum at 6.15 μg/L and minimum at 6150 μg/L. In the 5th day of exposed stage, the BCF of different tissues were the same with that in 7th day and came to a stable state. The trend of residual parameters was the same as BCF, and the maximum values were 1.62-171.11 in brain,0.17-155.44 in liver and 0.33-129.54 in gill during the whole recovery stage. The carbamazepine concentration in fish plasma increased with exposure concentration, and the increasing speed also had an improving trend. However, the BCF values decreased with the increasing concentration.