乙酸铜和阿维菌素对斜带石斑幼鱼毒性效应的研究

Toxic Effects of Cupric Acetate and Avermectins on Orange Spotted Grouper Epinephelus coioides

采用静水生物法,研究了乙酸铜和阿维菌素对斜带石斑鱼的急性毒性并进行安全评价;依据急性试验结果,设计一系列质量浓度梯度进行暴露试验,探讨了乙酸铜和阿维菌素暴露对斜带石斑鱼肝脏中乙酰胆碱酯酶、超氧化物歧化酶、谷草转氨酶活性和谷胱甘肽含量的毒性影响。试验结果表明,乙酸铜和阿维菌素对斜带石斑鱼的24h半致死质量浓度、48h半致死质量浓度分别为103.51、50.86mg/L和0.02543、0.01726mg/L,安全质量浓度分别为3.684mg/L和0.00239mg/L;除阿维菌素对谷草转氨酶作用不明显外,乙酸铜和阿维菌素胁迫均引起肝脏乙酰胆碱酯酶、超氧化物歧化酶和谷草转氨酶活性显著变化(P<0.05),与对照组相比,低质量浓度和短时间暴露时被诱导,随着暴露质量浓度和暴露时间的延长,抑制作用渐明显,高质量浓度时抑制显著(P<0.05);乙酸铜胁迫下,48h后大部分试验组(2mg/L、4mg/L和8mg/L)谷胱甘肽含量低于对照组(P>0.05),而96h后高于对照组(P<0.05),阿维菌素各暴露质量浓度组(2.5、4.25、7.25μg/L和12.25μg/L)谷胱甘肽含量显著低于对照组(P<0.05)。研究认为,乙酸铜和阿维菌素胁迫对乙酰胆碱酯酶、超氧化物歧化酶、谷草转氨酶活性和谷胱甘肽含量的影响,反映出对斜带石斑鱼机体的受损情况,为评价水产常用药对斜带石斑鱼的生物学效应提供科学依据。

In this study ,the activities of acetylcholinesterase （AChE） ,superoxide dismutase （SOD） ,and aspartate transaminase （GOT ） and glutathione （GSH ） content were studied in liver of orange spotted grouper Epinephelus coioides exposed to cupric acetate and Avermectins at various concentrations to evaluate acute toxicity of cupric acetate and Avermectins .The results showed that the 24 h LC50 and 48 h LC50 were 103 .51 mg/L and 50 .86 mg/L in cupric acetate and 0 .02543 mg/L and 0 .01726 mg/L in Avermectins , with safe concentration of 3 .684 mg/L for cupric acetate and 0 .00239 mg/L for Avermectins .Cupric acetate and Avermectins stress resulted in significant changes in AChE ,SOD ,and GOT activities in liver （P〈 0 .05） ,whereas Avermectins showed insignificant effects on GOT activity compared with control group . The AChE , SOD , and GOT activities were primarily induced at low concentration of cupric acetate and Avermectins in short term exposure ,and inhibited at high concentration of cupric acetate and Avermectins in long term exposure , with significantly （ P 〈 0 .05 ） at higher concentration .The lower liver GSH contents were in 2 mg/L ,4 mg/L and 8 mg/L groups than that in the control group in 48 h cupric acetate exposure（P〉0 .05） ,but higher than that in the control group in 96 h cupric acetate exposure （P〈 0 .05） .There were significantly lower liver GSH contents in 2 .5μg/L ,4 .25μg/L ,7 .25 μg/L and 12 .25 μg/L Avermectins groups than that in the control group . The findings indicate that cupric acetate and Avermectins stress affect AChE , SOD and GOT activities and GSH content ,and that biological effects of pesticides on orange spotted grouper are reflected in changes in activities of AChE ,SOD and GOT and GSH content .