【作者】 董怡飞； 田华； 王蔚； 张晓娜； 刘金相； 汝少国；

【Author】 Yifei Dong;Hua Tian;Wei Wang;Xiaona Zhang;Jinxiang Liu;Shaoguo Ru;College of Marine Life Sciences, Ocean University of China;

【机构】 中国海洋大学海洋生命学院；

【摘要】 褐牙鲆是我国重要的海洋经济鱼类,其发育历经特殊的变态过程。甲状腺激素(THs)在该过程中发挥着重要的作用,因此具有甲状腺干扰效应的众多污染物均可干扰褐牙鲆的变态从而影响其发育及产量。本研究选用典型的甲状腺干扰物—多氯联苯(PCBs)混合物Aroclor 1254,研究环境相关浓度(10、100、1000 ng/L)的PCBs暴露对褐牙鲆仔鱼变态过程的影响,同时从甲状腺组织学、血浆甲状腺激素水平(TT3、TT4、FT3、FT4水平)、三种脱碘酶(IDs,ID1、ID2和ID3)mRNA表达水平等指标的变化深入探讨了PCBs对褐牙鲆幼鱼甲状腺的干扰效应。结果表明:(1)PCBs暴露延迟了褐牙鲆仔鱼的变态过程并降低了其变态高峰期的THs水平。(2)褐牙鲆幼鱼暴露50天后甲状腺滤泡细胞出现明显的增生以及胶质缺损现象。(3)PCBs暴露褐牙鲆幼鱼50天后血浆TT4、TT3和FT3水平均显著下降。(4)PCBs使ID2 mRNA表达水平呈剂量依赖性升高。本研究表明环境相关浓度的PCBs可抑制褐牙鲆仔鱼的变态过程并引起褐牙鲆幼鱼甲状腺系统的紊乱。更多还原

【Abstract】 Japanese flounder(Paralichthys olivaceus), the important marine commercial fish in China, undergoes a special metamorphosis process which regulated by thyroid hormones(THs)specifically during its development. The contaminant has thyroid-disrupting properties could interfere with the metamorphosis of Japanese flounder, leading to abnormal development and reduced its yields eventually. This study used Aroclor 1254 to figure out the effects of environmentally relevant concentrations PCBs on larvae metamorphosis and discuss the thyroid disruption of juvenile Japanese flounder by examining thyroid histology, plasma THs(TT3, TT4,FT3, FT4) levels and quantifying mRNA expression levels of three deiodinase(ID1, ID2 and ID3).Results showed that(1) PCBs exposure delayed larvae metamorphosis and decreased THs levels at metamorphic climax.(2) Exposure to PCBs for 50 d increased thyroid follicular colloid depletion, and hyperplasia.(3) Exposure to PCBs for 50 d significantly decreased plasma TT4,TT3, and FT3 levels.(4) The expression level of ID2 mRNA in the liver exhibited a dose-dependent increase.更多还原