Abstract：
The 7-ethoxyresorufin-O-deethylase (EROD) activity was first time characterized in the neotropical fish Cnesterodon decemmaculatus as a biomarker for assessing environmental health in aquatic ecosystems of the Rio de la Plata Basin impacted by organic pollutants agonist of the aryl-hydrocarbon receptor (AhR). Both laboratory and field studies were conducted. Laboratory experiments were run using β-naphthoflavone (BNF) as an AhR agonist model. A clear concentration-response relationship was found between 1 and 100 μg/L, with a NOEC and LOEC of 1 and 10 μg/L. A fast time-dependent response was observed with a significant induction after 24 h and a plateau from 24 to 48 h up to 264 h of exposure. Differences in basal activity were found between juveniles, females, and males, but induction levels were similar. Both basal activities and induction levels were distinct in the whole body, liver, gill, muscle, brain, and embryos. Fold-change inductions in the respective tissues were: 20, 114, 3, 5, 1, and 14. Maternal transfer and early cyp1a activation were unveiled by embryonic induction. Clear differences in EROD activity were found among juveniles collected in hydrocarbon-polluted streams, beside the La Plata Petrochemical hub, and a reference stream. Similar EROD activities were observed in laboratory and feral fish, usually with values below or above 1,000 pmol/min x mg protein for unexposed or exposed organisms. The study contributes with original information about EROD activity in C. decemmaculatus that encourages the use of both the response as a robust biomarker of exposure and the species as a good sentinel organism to be included in surveillant programs for assessing aquatic pollution by AhR agonist chemicals within the Rio de la Plata Basin within the One Health paradigm.
摘要：
7-乙氧基间苯二酚-O-脱乙基酶（EROD）活性首次在新热带鱼类Cnesterodondemmaculatus中被表征为生物标志物，用于评估受有机污染物激动剂影响的里约普拉塔盆地水生生态系统的环境健康。芳烃受体（AhR）。进行了实验室和现场研究。使用β-萘并黄酮(BNF)作为AhR激动剂模型进行实验室实验。在1至100μg/L之间发现了明显的浓度-反应关系，NOEC和LOEC分别为1和10μg/L。观察到快速的时间依赖性反应，在24小时后有明显的诱导，从24到48小时到264小时的平稳期。发现青少年之间的基础活动差异，女性,和男性，但诱导水平相似。在整个身体中，基础活动和诱导水平都是不同的，肝脏,吉尔,肌肉，大脑,和胚胎。各个组织中的倍数变化诱导为：20、114、3、5、1和14。胚胎诱导揭示了母体移植和早期cyp1a激活。在碳氢化合物污染的溪流中收集的幼鱼中发现了EROD活性的明显差异，在拉普拉塔石化中心旁边，和参考流。在实验室和野生鱼类中观察到类似的EROD活动，对于未暴露或暴露的生物体，通常具有低于或高于1000pmol/minxmg蛋白质的值。该研究提供了有关C.demmaculatus中EROD活性的原始信息，该信息鼓励将该反应用作强大的暴露生物标志物，并将该物种用作良好的前哨生物，并纳入监测计划，以评估AhR激动剂化学物质的水生污染在“一个健康”范式中的拉普拉塔里约盆地。
