Centro de Ciências Biológicas e Sociais Aplicadas, Universidade Estadual da Paraíba, João Pessoa, Paraíba, Brazil.
Campus Centro-Oeste Dona Lindu, Universidade Federal de São João Del-Rei, Divinópolis, Minas Gerais, Brazil.
J Exp Zool A Ecol Integr Physiol. 2019 Dec;331(10):530-539. doi: 10.1002/jez.2320. Epub 2019 Sep 23.
We investigated the activity of the multixenobiotic resistance (MXR) phenotype, a biological defense system in aquatic organisms, in the fish assemblages of two tropical estuaries with different degrees of environmental impacts, the Paraiba River and Mamanguape River Estuaries. The aim of this work was to compare the activity of the MXR phenotype of different fishes to test the hypothesis that each species has an inherent activity level and to use this activity as a bioindicator of aquatic contamination. We assessed the MXR activity of the gills, using rhodamine B (RB) accumulation assay. The results demonstrated a species-specific difference in the MXR activity of fishes caught in the same estuarine zone. Also, the pelagic species Eucinostomus melanopterus, Eucinostomus argenteus, and Lutjanus jocu had higher RB accumulation, while the demersal species Sphoeroides testudineus and Sphoeroides greeleyi had the lowest RB accumulation, suggesting that the ecological characteristic of fish in the water column exerts an influence on MXR activity. Besides, we demonstrated the potential of using the gill MXR activity of the key estuarine species, the Brazilian silversides Atherinella brasiliensis, as a tool for biomonitoring estuaries.
我们研究了多药耐药（MXR）表型的活性，这是水生生物的一种生物防御系统，在两个具有不同环境影响程度的热带河口的鱼类群落中进行了研究，这两个河口分别是 Paraiba 河和 Mamanguape 河河口。这项工作的目的是比较不同鱼类的 MXR 表型活性，以检验每个物种都具有固有活性水平的假设，并将这种活性用作水生污染的生物指标。我们使用罗丹明 B（RB）积累测定法评估了鳃中的 MXR 活性。结果表明，在同一河口区域捕获的鱼类中，MXR 活性存在种特异性差异。此外，中上层鱼类 Eucinostomus melanopterus、Eucinostomus argenteus 和 Lutjanus jocu 的 RB 积累较高，而底层鱼类 Sphoeroides testudineus 和 Sphoeroides greeleyi 的 RB 积累较低，这表明鱼类在水柱中的生态特征对 MXR 活性有影响。此外，我们证明了使用关键河口物种巴西银汉鱼（Atherinella brasiliensis）的鳃 MXR 活性作为河口生物监测工具的潜力。
