Sepúlveda María S, Gallagher Evan P, Wieser Carla M, Gross Timothy S
Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL 32610, USA.
Ecotoxicol Environ Saf. 2004 Mar;57(3):431-40. doi: 10.1016/j.ecoenv.2003.08.020.
The objective of this study was to evaluate the effects of bleached/unbleached kraft mill effluents (B/UKME) on the reproductive parameters of free-ranging Florida largemouth bass (Micropterus salmoides floridanus). The reproductive parameters measured included gonadosomatic index (GSI), histological evaluation of gonads, and plasma concentrations of vitellogenin (VTG), 17beta-estradiol, and 11-ketotestosterone (11-KT). Hepatic ethoxyresorufin-O-deethylase (EROD) activity was measured as a marker of exposure to cytochrome P450-inducing agents in these effluents. Endpoints were compared among adult bass sampled from tributary and mainstream effluent-contaminated and reference sites. Females sampled from the site closest to the mill outfall had a significant five-fold increase in EROD activity compared to bass sampled from reference streams. Although sex hormones were significantly reduced in bass from exposed sites, there were no differences in VTG and GSI across sites. The absence of organism-level responses was probably not related to a lack of sensitivity, as previous studies in our laboratory have shown that bass exposed to these effluents exhibit changes in GSI and in other measures associated with reproductive success. In females, inverse relationships were observed between VTG and GSI and EROD activity. These relationship, however, were not consistent within all of the sites studied. Collectively, our findings indicate that hepatic EROD induction is an effective marker of B/UKME exposure in largemouth bass and that it might be associated with antiestrogenic effects in this species.
本研究的目的是评估漂白/未漂白硫酸盐制浆厂废水（B/UKME）对佛罗里达野生大口黑鲈（Micropterus salmoides floridanus）繁殖参数的影响。所测量的繁殖参数包括性腺指数（GSI）、性腺组织学评估以及血浆中卵黄蛋白原（VTG）、17β-雌二醇和11-酮睾酮（11-KT）的浓度。测量肝脏乙氧基异吩恶唑酮-O-脱乙基酶（EROD）活性，作为这些废水中细胞色素P450诱导剂暴露的标志物。对从支流和主流受废水污染的地点以及参考地点采集的成年鲈鱼的各项指标进行比较。与从参考溪流采集的鲈鱼相比，从最靠近工厂排水口的地点采集的雌性鲈鱼的EROD活性显著增加了五倍。尽管暴露地点的鲈鱼性激素显著降低，但各地点的VTG和GSI没有差异。生物水平反应的缺乏可能与缺乏敏感性无关，因为我们实验室之前的研究表明，暴露于这些废水的鲈鱼在GSI以及与繁殖成功相关的其他指标上表现出变化。在雌性中，观察到VTG与GSI和EROD活性之间呈负相关。然而，这些关系在所有研究地点并不一致。总体而言，我们的研究结果表明，肝脏EROD诱导是大口黑鲈暴露于B/UKME的有效标志物，并且它可能与该物种的抗雌激素作用有关。
