Richards S M, Kelly S E, Hanson M L
Department of Biologic and Environmental Sciences, University of Tennessee-Chattanooga, Chattanooga, TN 37403, USA.
Arch Environ Contam Toxicol. 2008 May;54(4):637-44. doi: 10.1007/s00244-007-9062-9.
Numerous human and veterinary pharmaceuticals are constantly entering surface waters, despite little understanding of their potential impacts on aquatic ecosystems. To address this concern, an attempt to create a simple, reproducible, inexpensive, and sublethal toxicity bioassay for freshwater zooplankton was initiated. The approach was centered on characterizing the response of a zooplankton enzyme, chitobiase, to the presence of a toxicant. The aim of the present research was to develop a reproducible laboratory-based assay for Daphnia magna chitobiase activity and to screen four commonly prescribed pharmaceuticals using that assay. The four pharmaceuticals tested for potential effects on D. magna chitobiase activity were atorvastatin, lovastatin, fluoxetine, and sertraline. We were able to detect exposure-associated differences in chitobiase activity at concentrations of 0.1 mug/L fluoxetine after 24 and 72 hours of exposure. Differences were also detected for the other compounds. The response of chitobiase was found to be promising as an assay to measure sublethal effects in D. magna and perhaps other zooplankton species.
尽管对众多人类和兽用药物对水生生态系统的潜在影响了解甚少，但它们仍在不断进入地表水。为解决这一问题，我们开始尝试为淡水浮游动物创建一种简单、可重复、低成本且具有亚致死毒性的生物测定方法。该方法的核心是表征浮游动物酶——壳二糖酶对有毒物质存在的反应。本研究的目的是开发一种基于实验室的可重复测定大型溞壳二糖酶活性的方法，并使用该方法筛选四种常用处方药。测试对大型溞壳二糖酶活性有潜在影响的四种药物分别是阿托伐他汀、洛伐他汀、氟西汀和舍曲林。在暴露24小时和72小时后，我们能够检测到浓度为0.1微克/升的氟西汀下壳二糖酶活性与暴露相关的差异。其他化合物也检测到了差异。结果发现，壳二糖酶的反应有望作为一种测定大型溞以及可能其他浮游动物物种亚致死效应的方法。
