Doyle Christopher J, Lim Richard P
Department of Environmental Sciences, University of Technology Sydney, P.O. Box 123, Broadway, New South Wales 2007, Australia.
Environ Toxicol Chem. 2002 Dec;21(12):2719-24.
Many chemicals have recently been demonstrated to possess estrogenic activity and may potentially interfere with normal sexual development. In the present study, we quantified the effects of waterborne exposure to 17beta-estradiol on the gonopodial development and sexual activity of male eastern mosquitofish (Gambusia holbrooki). Juvenile males were exposed during the period of sexual maturation to nominal concentrations of 20, 100, and 500 ng/L of 17beta-estradiol and a solvent control (0.00003% w/v ethanol) for 84 d under continuous-flow conditions. Following exposure, significant differences were found among the test treatments with respect to gonopodial length and degree of gonopodial elongation of the fish. Sexual activity, measured as the number of approaches and copulatory attempts made by the exposed males to nonexposed females, also significantly decreased with increasing concentrations of 17beta-estradiol. Because the degree of gonopodial maturation and frequency of sexual activity are important characteristics for the reproductive success of male mosquitofish, it is suggested that these traits provide sensitive and ecologically relevant endpoints for assessing estrogenic activity under both laboratory--and field-exposure conditions.
最近已证实许多化学物质具有雌激素活性，并可能潜在地干扰正常的性发育。在本研究中，我们量化了水体暴露于17β-雌二醇对雄性东部食蚊鱼（Gambusia holbrooki）交接器发育和性行为的影响。在性成熟期间，将幼年雄性食蚊鱼暴露于名义浓度为20、100和500 ng/L的17β-雌二醇以及溶剂对照（0.00003% w/v乙醇）中，在连续流动条件下处理84天。暴露后，在受试处理组之间，鱼的交接器长度和交接器伸长程度存在显著差异。以暴露雄性对未暴露雌性的接近次数和交配尝试次数衡量的性行为，也随着17β-雌二醇浓度的增加而显著降低。由于交接器成熟程度和性行为频率是雄性食蚊鱼繁殖成功的重要特征，因此建议这些特征为评估实验室和野外暴露条件下的雌激素活性提供敏感且与生态相关的终点指标。
