Roling Jonathan A, Baldwin William S
University of Texas at El Paso, Biological Sciences, El Paso, TX 79968, USA.
Mar Environ Res. 2006 Jul;62 Suppl(Suppl):S122-7. doi: 10.1016/j.marenvres.2006.04.008. Epub 2006 Apr 7.
Cr(III) is the dominant toxicant at some Superfund sites within the United States and therefore we are interested in its effects. Cr(III)s mechanisms are not well studied or understood because of its low bioavailability. We have attempted to characterize the effects of Cr(III) on gene expression in Fundulus heteroclitus (mummichog) liver. The NOEC and LOEC were determined at 32 and 64 mg/L, respectively, by measuring growth and mortality after exposing juveniles for 30 days. Secondary adult male exposures were performed at 32 mg/L, livers excised, and RNA extracted. Arrays were probed with cDNA from untreated or Cr(III)-exposed adult fish and gene expression was quantified. Cr(III) at 32 mg/L altered the expression of five genes, including GSTtau, GSTalpha, and ALDH4. Ultimately, we anticipate using this gene expression information to ascertain whether Cr(III) is bioavailable at potentially adverse concentrations in contaminated sites.
在美国，三价铬是一些超级基金污染场地中的主要有毒物质，因此我们对其影响很感兴趣。由于三价铬的生物利用度较低，其作用机制尚未得到充分研究或理解。我们试图表征三价铬对底鳉肝脏基因表达的影响。通过在幼鱼暴露30天后测量生长和死亡率，分别确定了无观察效应浓度（NOEC）和最低观察效应浓度（LOEC）为32毫克/升和64毫克/升。对成年雄性进行了32毫克/升的二次暴露，切除肝脏并提取RNA。用来自未处理或三价铬暴露成年鱼的cDNA对微阵列进行检测，并对基因表达进行定量。32毫克/升的三价铬改变了五个基因的表达，包括谷胱甘肽S-转移酶tau（GSTtau）、谷胱甘肽S-转移酶alpha（GSTalpha）和醛脱氢酶4（ALDH4）。最终，我们期望利用这些基因表达信息来确定在受污染场地中，处于潜在有害浓度的三价铬是否具有生物可利用性。
