The low brominated polybrominated diphenyl ether (PBDE) 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) is ubiquitous in the marine environment. To elucidate the stress response and possible mechanisms underlying BDE-47, the rainbow trout fish Oncorhynchus mykiss were selected and orally fed bait with BDE-47 concentrations of 50 ng/g and 500 ng/g. BDE-47 was found to be mainly accumulated in head kidney and caused lipid peroxidation after prolonged exposure. We studied the detoxification system genes pregnane X receptor (PXR) and downstream genes (cytochrome 3 A, CYP3 A; glutathione S-transferase, GST) and their corresponding enzyme activity and found that the above indicators in the treatment groups increased first and then decreased with time, while the 500 ng/g group showed more significant changes. Further, the antioxidant system gene expression levels of the NF-E2-related factor 2 (Nrf2) and downstream genes (superoxide dismutase, SOD; catalase, CAT) were found significantly up-regulated with concentration and time. The change in the enzyme activity of SOD and CAT showed the same tendency as that of indicators of detoxifying system. The results showed that BDE-47 can accumulated in head kidney and caused activate and fast increase of genes and enzymes of detoxification and antioxidant system in the short-term and then damage the response systems in longer times. After Pearson correlation analysis, the Integrated Biomarker Response (IBR) Index was established with malondialdehyde (MDA) content; PXR, Nrf2, SOD, and CAT gene expression; and CYP3 A, GST, and CAT enzymatic activity, which were significantly related to BDE-47 bioaccumulation (P < 0.5). The IBR value can indicate the ecotoxicological responses of the head kidney to different BDE-47 concentrations exposure, but the high activity of the antioxidant system might obscure the damage of the detoxification system.

低溴化多溴联苯醚（PBDE）2,2'，4,4'-四溴二苯醚（BDE-47）在海洋环境中无处不在。为阐明虹鳟鱼Oncorhynchus mykiss对BDE-47的压力反应及可能的机制选择被捕食的BDE-47浓度分别为50 ng / g和500 ng / g的饵料。发现BDE-47主要积累在头肾中，长时间接触会引起脂质过氧化。我们研究了排毒系统基因孕烷X受体（PXR）和下游基因（细胞色素3 A，CYP3 A；谷胱甘肽S-转移酶，GST）及其相应的酶活性，发现治疗组中的上述指标先升高后降低随着时间的推移，而500 ng / g组显示出更显着的变化。此外，发现NF-E2相关因子2（Nrf2）和下游基因（超氧化物歧化酶，SOD；过氧化氢酶，CAT）的抗氧化剂系统基因表达水平随浓度和时间显着上调。SOD和CAT的酶活性变化与排毒系统指标变化趋势相同。结果表明，BDE-47可在头部肾脏中蓄积，并在短期内引起排毒和抗氧化系统的基因和酶的激活和快速增加，并在更长的时间内破坏响应系统。经过Pearson相关分析，建立了丙二醛（MDA）含量的综合生物标志物反应（IBR）指数；PXR，Nrf2，SOD和CAT基因表达；CYP3A，GST和CAT的酶活性与BDE-47的生物蓄积显着相关（P <0.5）。IBR值可以表明头肾对不同BDE-47浓度暴露的生态毒理反应，