三种磺胺类药物对罗非鱼肝脏组织中谷胱甘肽转移酶(GST)和丙二醛(MDA)的影响

Effects of three typical sulfonamides on GST activity and MDA content in liver tissue of Oreochromis niloticus

研究磺胺嘧啶(sulfadianzine,SDZ)、磺胺二甲基嘧啶(sulfadimidine,SM2)和磺胺甲基异恶唑(sulfamethoxazole,SMZ)三种典型磺胺类抗生素对罗非鱼(Oreochromis niloticus)肝脏谷胱甘肽转移酶(GST)活性和丙二醛(MDA)含量的响应。采用饲料暴露的给药方式,用磺胺药物浓度为4和40g·kg-1的人工配合饲料喂养试验罗非鱼,对照组投喂不含磺胺药物的空白饲料。暴露时间为7d,每天2次投喂饲料,饲料的日投喂量按鱼体重的3%计,分别在24、72和168h采集肝脏样品待测。结果表明各浓度组GST和MDA分别在暴露后72和24h受到最大程度的诱导,其中GST活性比空白组提高了6.72倍,MDA含量比空白组提高了24.75倍。在4g·kg-1的药物浓度下SM2对GST和MDA有最强诱导,在40g·kg-1的药物浓度下三种药物对罗非鱼GST和MDA诱导效应大小顺序为SDZ>SMZ>SM2。GST和MDA在磺胺药物诱导下的响应敏感,适合作为磺胺类药物暴露的生物标记物。

GST enzyme activity and MDA content in liver tissue of Oreochromis niloticus were investigated by feeding exposure experiment with three typical sulfonamides.The Oreochromis niloticus of exposure group were fed by artificial fishfood with sul- fonamides in concentration of 4 g·kg -1 and 40 g·kg -1 ,and the control group were fed by fishfood without sulfonamides.The exposure period was 7 days.The tilapia were fed twice a day with a certain amount of fishfood equivalent to 3%of total body weight.The liver tissue of the tilapia were sampled and prepared for the test of GST activity and MDA content after being exposed by 24 h、72 h and 168 h respectively.The results indicated that GST and MDA were induced by sulfonamides and reached the highest value at 72 h and 24 h exposure respectively.GST activity and MDA content were increased by 6.72 and 24.75 times comparing with the control experiment.GST and MDA were induced most under the treatment of SM2 concentration of 4 g·kg -1 .The inductive effect of three sulfonamides on GST and MDA under 40 g·kg -1 exposure were as following：SDZSMZSM2.GST and MDA may act as the sensitive and potential biomarkers of sulfonamides contamination in aquatic environment.