Coe Tobias S, Hamilton Patrick B, Hodgson David, Paull Gregory C, Stevens Jamie R, Sumner Katie, Tyler Charles R
Ecotoxicology and Aquatic Biology Research Group, University of Exeter, Exeter, UK.
Environ Sci Technol. 2008 Jul 1;42(13):5020-5. doi: 10.1021/es800277q.
There is global concern regarding the potential impacts of endocrine-disrupting chemicals (EDCs) on the health of wildlife and humans. Exposure to some estrogens, at concentrations found in the environment impairs reproductive function and behavior. However, nearly all work on endocrine disruption has investigated the effects of exposure on individuals and there is an urgent need to understand impacts on populations. Many fish have mating systems with complex social structures and it is not known whether EDCs will exaggerate or buffer the reproductive skews caused by the dominance hierarchies that normally occur for these species. This study investigated the impact of exposure to the pharmaceutical estrogen ethinylestradiol (EE2) on reproductive hierarchies and sexual selection in group-spawning fish. Breeding zebrafish were exposed to environmentally relevant concentrations of EE2, and effects were determined on reproductive output, plasma androgen concentrations (in males), and reproductive success through microsatellite analyses of the offspring. Reproductive hierarchies in breeding colonies of zebrafish were disrupted by exposure to EE2 at a concentration that did not affect the number of eggs produced. The effect was a reduction in the skew in male paternity and increased skew in female maternity. This disruption in the reproductive hierarchy in group spawning fish, if it occurs in the wild, has potentially major implications for population genetic diversity. Reproductive success in male zebrafish was associated with elevated plasma concentrations of the male sex hormone 11-ketotestosterone and this hormone was suppressed in EE2-exposed males.
内分泌干扰化学物质（EDCs）对野生动物和人类健康的潜在影响引起了全球关注。接触环境中发现的某些雌激素浓度会损害生殖功能和行为。然而，几乎所有关于内分泌干扰的研究都调查了暴露对个体的影响，因此迫切需要了解对种群的影响。许多鱼类具有复杂社会结构的交配系统，目前尚不清楚EDCs是否会加剧或缓冲这些物种通常存在的优势等级制度所导致的生殖偏差。本研究调查了暴露于药物雌激素乙炔雌二醇（EE2）对群体产卵鱼类生殖等级和性选择的影响。将繁殖期的斑马鱼暴露于与环境相关浓度的EE2中，并通过对后代的微卫星分析来确定对生殖产量、血浆雄激素浓度（雄性）和生殖成功率的影响。斑马鱼繁殖群体中的生殖等级因暴露于不影响产卵数量的浓度的EE2而受到干扰。结果是雄性亲权偏差减少，雌性母权偏差增加。如果在野外发生这种群体产卵鱼类生殖等级的干扰，可能对种群遗传多样性产生重大影响。雄性斑马鱼的生殖成功与雄性性激素11-酮睾酮的血浆浓度升高有关，而在暴露于EE2的雄性中这种激素受到抑制。
