Ecotoxicology and Environmental Fish Health Program, Environmental Conservation Division, Northwest Fisheries Science Center, National Marine Fisheries Service, NOAA, 2725 Montlake Blvd. East, Seattle, WA 98112, USA.
Environ Res. 2011 Jan;111(1):50-6. doi: 10.1016/j.envres.2010.11.012. Epub 2010 Dec 16.
We conducted a dietary feeding study with juvenile chinook salmon (Oncorhynchus tshawytscha) to assess the potential for tributyltin (TBT) to elicit the obesogen response that has been described for mammals. The results show increases in whole-body lipid content, which is consistent with the obesogen response; however, we also observed associated parameters that were dissimilar. We found increases in body mass and alterations to several physiological parameters at doses between 0.4 and 3.5 ng/g fish/day (1.4-12 pmol/g fish/day) and reduced body mass at the highest dose after 55 days of exposure. Lipid related plasma parameters (plasma triacylglycerols, cholesterol, and lipase) exhibited monotonic increases over all doses while other values (glucose and insulin-like growth factor (IGF)) exhibited increases only for the low-dose treatments. The increases noted for several parameters in fish were opposite to those reported for the obesogen metabolic syndrome, which is characterized by a reduction in serum glucose, free fatty acids, and triglycerides. This is the first report of growth stimulation resulting from low-dose exposure to this pesticide, which is an unusual response for any animal exposed to an organic or organometallic xenobiotic. Because a number of environmental contaminants act as metabolic disruptors at very low doses, these results are noteworthy for a variety of species. Intuitively, enhanced growth and lipid storage may appear beneficial; however, for salmonids there are numerous potentially negative consequences for populations.
我们进行了一项关于幼年奇努克鲑鱼（Oncorhynchus tshawytscha）的饮食喂养研究，以评估三丁基锡（TBT）是否会引发已在哺乳动物中描述的致肥胖反应。结果表明，全身脂肪含量增加，这与致肥胖反应一致；然而，我们也观察到了一些不同的相关参数。我们发现，在 0.4 至 3.5ng/g 鱼/天（1.4-12pmol/g 鱼/天）的剂量下，体重增加和几种生理参数发生变化，而在 55 天暴露后，在最高剂量下体重减轻。脂质相关的血浆参数（血浆三酰甘油、胆固醇和脂肪酶）在所有剂量下均呈单调增加，而其他值（葡萄糖和胰岛素样生长因子（IGF））仅在低剂量处理下增加。鱼类中几个参数的增加与肥胖代谢综合征的报道相反，肥胖代谢综合征的特征是血清葡萄糖、游离脂肪酸和甘油三酯减少。这是首次报道由于低剂量接触这种农药而导致生长刺激，这对于任何接触有机或有机金属外来生物的动物来说都是一种异常反应。由于许多环境污染物在极低剂量下就会作为代谢干扰物发挥作用，因此这些结果对各种物种都具有重要意义。直观地说，增强的生长和脂肪储存可能看起来是有益的；然而，对于鲑鱼来说，这对种群有许多潜在的负面影响。
