Specimens of two endemic cyprinids, Squalius laietanus (Catalan chub) and Barbus meridionalis (Mediterranean barbel), were sampled from a reference site in a small stream of the Ripoll River (NW Mediterranean) outside of their reproductive season. Biomarkers involved in xenobiotic-mediated responses were individually contrasted in fish of both species and 17 perfluoroalkyl substances (PFASs) analysed in muscle to reveal bioaccumulation trends. The parameters were in muscle: cholinesterases, metabolic lactate dehydrogenase (LDH) and citrate synthase (CS); and in liver: cytochrome P450 dependent activities (EROD and BFCOD), carboxylesterase (CE), glutathione S-transferase (GST), glutathione reductase (GR), glutathione peroxidase (GPX) and catalase (CAT). All markers are considered adaptive defence mechanism to face stress. Sensitivity to a model pesticide: dichlorvos was also contrasted in vitro in muscular acetylcholinesterase (AChE) and hepatic CE to reveal species sensitivity to neurotoxic chemicals. Enzymatic activities related to protective mechanisms such as butyrylcholinesterase (BuChE), CE and CAT were higher in chub whereas the antioxidant defences GR and GPX were higher in barbel. Aerobic CS was also higher in barbel while anaerobic LDH was so in chub. EROD activity did not differ between the two species but BFCOD activity was higher in barbel. Levels of PFAS were higher in barbel likely due to its benthic habitat. The in vitro tests revealed higher sensitivity to dichlorvos of muscular AChE in chub (lower IC50) which was probably compensated by a higher catalytic efficiency of CE. All these former biochemical particularities are discussed in terms of fish ecological performance in front of anthropogenic stressors.

在繁殖季节以外的里波尔河（地中海西北部）的一条小溪中，从一个参考点采集了两个地方性鲤科的标本，它们是Squalius laietanus（Catalan chub）和Barbus meridionalis（Mediterranean barbel）。异种生物介导的反应中涉及的生物标记在两种鱼类中分别进行了对比，并在肌肉中分析了17种全氟烷基物质（PFAS），以揭示生物蓄积趋势。参数在肌肉中：胆碱酯酶，代谢性乳酸脱氢酶（LDH）和柠檬酸合酶（CS）；在肝脏中：细胞色素P450依赖性活性（EROD和BFCOD），羧酸酯酶（CE），谷胱甘肽S-转移酶（GST），谷胱甘肽还原酶（GR），谷胱甘肽过氧化物酶（GPX）和过氧化氢酶（CAT）。所有标记都被认为是面对压力的自适应防御机制。对模型农药的敏感性：敌敌畏在肌肉乙酰胆碱酯酶（AChE）和肝CE中也进行了体外对比，以揭示物种对神经毒性化学物质的敏感性。与保护机制相关的酶活性，例如丁酰胆碱酯酶（BuChE），CE和CAT在中较高，而抗氧化防御GR和GPX在bar中较高。杠铃中的有氧CS也较高，而厌氧中的LDH则较高。两种物种的EROD活性没有差异，但杠铃的BFCOD活性较高。由于其底栖生境，通货膨胀症的全氟辛烷磺酸水平较高。在体外测试显示，对中肌肉AChE的敌敌畏有较高的敏感性（较低的IC50），这可能是由于CE的较高催化效率所补偿。所有这些以前的生化特性都在人为压力源面前的鱼类生态性能方面进行了讨论。