Schweizer K, Wagner C A, Geis-Gerstorfer J, Lang F
Department of Physiology I, University of Tuebingen, Germany.
J Dent Res. 2001 Aug;80(8):1753-7. doi: 10.1177/00220345010800081401.
Mercury was previously shown to exert toxic effects by influencing ion channels and transporters in the kidney and brain. Gallium alloys were suggested as less toxic restorative materials. To compare the toxicity of gallium ions with those of mercury ions, we applied gallium nitrate Ga(NO3)3 (0.1-100 microM and mercuric chloride (HgCl2) (0.001-10 microM) to Xenopus oocytes expressing mammalian ion channels and transport proteins. Mercury (10 microM) inhibited the K+-channels ROMK and HERG, the phosphate transporter NaPi-3, the amino acid transporter rBAT, the cation transporter OCT-2, and the osmolyte transporter BGT. It activated the I(Ks)-channel but did not affect the Na+-channel ENaC, the anion channel NaPi-1, and the glucose transporter SGLT-1. Gallium was without significant effect on the channels and on SGLT1, NaPi-3, and rBAT, but inhibited BGT and OCT-2. In conclusion, both Hg2+ and Ga3+ may exert toxic effects on transport systems, which may partially explain their cytotoxic effects.
先前研究表明，汞可通过影响肾脏和大脑中的离子通道及转运蛋白发挥毒性作用。镓合金被认为是毒性较低的修复材料。为比较镓离子与汞离子的毒性，我们将硝酸镓Ga(NO3)3（0.1 - 100微摩尔）和氯化汞(HgCl2)（0.001 - 10微摩尔）应用于表达哺乳动物离子通道和转运蛋白的非洲爪蟾卵母细胞。汞（10微摩尔）抑制钾通道ROMK和HERG、磷酸盐转运蛋白NaPi - 3、氨基酸转运蛋白rBAT、阳离子转运蛋白OCT - 2以及渗透溶质转运蛋白BGT。它激活了I(Ks)通道，但不影响钠通道ENaC、阴离子通道NaPi - 1和葡萄糖转运蛋白SGLT - 1。镓对这些通道以及SGLT1、NaPi - 3和rBAT没有显著影响，但抑制了BGT和OCT - 2。总之，Hg2+和Ga3+都可能对转运系统产生毒性作用，这可能部分解释了它们的细胞毒性作用。
