Rutherford Robert, Lister Andrea, Hewitt L Mark, MacLatchy Deborah
Department of Biology, Wilfrid Laurier University, 75 University Avenue West, Waterloo, ON N2L 3C5, Canada.
Department of Biology, Wilfrid Laurier University, 75 University Avenue West, Waterloo, ON N2L 3C5, Canada.
Comp Biochem Physiol C Toxicol Pharmacol. 2015 Apr;170:8-18. doi: 10.1016/j.cbpc.2015.01.004. Epub 2015 Jan 26.
Androgens originating from pulp mill processing, sewage treatment facilities and agricultural activities have the potential for discharge into aquatic receiving environments. To assess androgen effects on reproductive endocrine status in fish in estuarine environments, male and female adult northern mummichog (Fundulus heteroclitus macrolepidotus) were exposed to an aromatizable androgen (17α-methyltestosterone; MT) and a non-aromatizable androgen (5α-dihydrotestosterone; DHT) in a short-term reproductive endocrine bioassay. Fish were nominally exposed to 10 μg/L or 100 μg/L DHT, or 0.1 μg/L or 1 μg/L MT for 14 days during gonadal recrudescence. Actual concentrations of androgens, as measured by enzyme immunoassay (EIA), were 10-49% of nominal MT 0.1, 3-6% of nominal MT 1, 5-10% of nominal DHT 10 and 3-25% of nominal DHT 100. Female mummichog were impacted to a greater degree by androgen exposure, with increased plasma testosterone (T) at 100 μg/L DHT, depressed plasma 17β-estradiol (E2) at both DHT concentrations and at 1 μg/L MT, as well as depressed in vitro E2 at both MT concentrations and 100 μg/L DHT. Males had depressed plasma T in the 10 μg/L DHT treatment and depressed in vitro 11-ketotestosterone production for both MT concentrations and 10 μg/L DHT. Ovarian aromatase gene expression was induced in females exposed to 1 μg/L MT. DHT at 100 μg/L increased hepatic vitellogenin-1 (VTG1) expression in males and depressed VTG1 expression in females. The range of responses between sexes and among species provides evidence for modes of actions and potential impacts of androgens in aquatic receiving environments.
源自纸浆厂加工、污水处理设施和农业活动的雄激素有可能排放到水生接收环境中。为了评估雄激素对河口环境中鱼类生殖内分泌状态的影响，在一项短期生殖内分泌生物测定中，将成年雄性和雌性北方鳉鱼（Fundulus heteroclitus macrolepidotus）暴露于一种可芳香化的雄激素（17α-甲基睾酮；MT）和一种不可芳香化的雄激素（5α-双氢睾酮；DHT）中。在性腺再发育期间，鱼类名义上暴露于10μg/L或100μg/L的DHT，或0.1μg/L或1μg/L的MT中14天。通过酶免疫测定（EIA）测量的雄激素实际浓度为名义MT 0.1的10 - 49%、名义MT 1的3 - 6%、名义DHT 10的5 - 10%和名义DHT 100的3 - 25%。雄激素暴露对雌性鳉鱼的影响更大，在100μg/L DHT时血浆睾酮（T）升高，在两种DHT浓度以及1μg/L MT时血浆17β-雌二醇（E2）降低，并且在两种MT浓度和100μg/L DHT时体外E2降低。在10μg/L DHT处理中雄性血浆T降低，在两种MT浓度和10μg/L DHT时体外11-酮睾酮生成降低。在暴露于1μg/L MT的雌性中，卵巢芳香化酶基因表达被诱导。100μg/L的DHT增加了雄性肝脏卵黄蛋白原-1（VTG1）的表达并降低了雌性VTG1的表达。两性之间以及物种之间的反应范围为雄激素在水生接收环境中的作用模式和潜在影响提供了证据。
