Department of Bio- and Environmental Sciences, University of Helsinki, P.O. Box 65, FI-00014 Helsinki, Finland.
Aquat Toxicol. 2010 May 10;97(4):285-92. doi: 10.1016/j.aquatox.2009.12.015. Epub 2009 Dec 21.
Endocrine disrupting chemicals (EDCs) are a diverse group of compounds that can mimic, block or modulate the synthesis of natural hormones. They are known to cause impairment of reproduction of aquatic organisms at very low concentrations. The aim of this study was to examine how exposure from 10 to 31 days to 17alpha-ethinyl estradiol (EE2, 41 ng L(-1)) affects the courtship and parental care behaviour of male sand gobies (Pomatoschistus minutus). The sand goby exhibits a polygynous mating system, where males compete for females and provide paternal care. First, male courtship performance towards a stimulus female was recorded with video camera. Secondly, after the male had received eggs his parental care behaviour was video recorded. In addition to behavioural endpoints, we measured the expression of hepatic vitellogenin (Vtg) and zona radiata protein (Zrp) mRNA, as well as common somatic indices. Our study shows that exposure to EE2 affected male fanning behaviour during both courtship and parental care. Interestingly, small exposed males increased their courtship fanning to similar levels as larger control males. However, during parental care egg fanning was not related to male size, and all exposed males fanned more than control males. The EE2-exposure induced Vtg and Zrp mRNA expression in males and decreased hepatosomatic index (HSI), and increased gonadosomatic index (GSI). Females prefer males that fan more, which will favour the small EDC exposed males. This may lead to mating that favours males that are not strong enough to tend the eggs until they hatch, thus decreasing the reproductive success of individuals.
内分泌干扰化学物质（EDCs）是一类能够模拟、阻断或调节天然激素合成的化合物。它们已知会在非常低的浓度下损害水生生物的生殖能力。本研究旨在探讨 17α-乙炔基雌二醇（EE2，41ng/L）暴露 10-31 天对雄性沙鲷（Pomatoschistus minutus）求偶和育雏行为的影响。沙鲷表现出多配偶制的交配系统，其中雄性竞争雌性并提供亲代照顾。首先，使用摄像机记录雄性对刺激雌性的求偶行为。其次，雄性接受卵子后，对其亲代照顾行为进行视频记录。除了行为终点外，我们还测量了肝脏卵黄蛋白原（Vtg）和卵黄膜蛋白（Zrp）mRNA 的表达，以及常见的体指数。我们的研究表明，EE2 暴露会影响雄性在求偶和育雏期间的扇动行为。有趣的是，暴露的小雄性将它们的求偶扇动增加到与大对照组雄性相似的水平。然而，在育雏期间，卵的扇动与雄性大小无关，所有暴露的雄性都比对照组雄性扇动更多。EE2 暴露会诱导雄性的 Vtg 和 Zrp mRNA 表达，并降低肝体指数（HSI），增加性腺体指数（GSI）。雌性更喜欢扇动更多的雄性，这将有利于受到 EDC 暴露的小雄性。这可能导致交配有利于不够强壮的雄性，无法在卵孵化前照顾它们，从而降低个体的繁殖成功率。
