Key Laboratory of Grassland Agro-ecosystem, Ministry of Agriculture, School of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, People's Republic of China.
Biol Trace Elem Res. 2011 Mar;139(3):356-67. doi: 10.1007/s12011-010-8662-9. Epub 2010 Mar 30.
To investigate the effects of amiloride, which is an inhibitor of Na(+)/H(+) antiporter (NHX), on Na(+) accumulation and transport at the whole plant level, in this study, 3-week-old Zygophyllum xanthoxylum plants were exposed to 25, 50 and 100 mM NaCl with or without 0.5 mM amiloride. After 72 h of treatment, dry weight, tissue water content, Na(+) and K(+) concentrations, and transcript levels of ZxNHX were determined. The results indicated that, under salt conditions, leaf Na(+) concentration, total Na(+) quantity and root net Na(+) uptake rate in plants treated with amiloride are significantly lower than those in control plants. Amiloride remarkably increased Na(+) proportion in stem and decreased Na(+) proportion in leaf of Z. xanthoxylum. Furthermore, our results showed that the transcript levels of ZxNHX are down-regulated by amiloride. It is clear that the inhibition of vacuolar Na(+)/H(+) antiporter by amiloride could disrupt Na(+) accumulation of leaf, and reduce Na(+) uptake by root and Na(+) transport from stem to leaf, thus resulting in the growth inhibition of Z. xanthoxylum exposed to salt.
为了研究阿米洛利（一种 Na(+)/H(+) 反向转运蛋白（NHX）抑制剂）对整株植物水平 Na(+) 积累和转运的影响，本研究将 3 周大的蒺藜木（Zygophyllum xanthoxylum）暴露于 25、50 和 100 mM NaCl 中，同时或不添加 0.5 mM 阿米洛利。处理 72 h 后，测定干重、组织含水量、Na(+)和 K(+)浓度以及 ZxNHX 的转录水平。结果表明，在盐胁迫条件下，用阿米洛利处理的植物叶片 Na(+)浓度、总 Na(+)量和根净 Na(+)摄取率显著低于对照植物。阿米洛利显著增加了茎中 Na(+)的比例，降低了叶片中 Na(+)的比例。此外，我们的结果表明，阿米洛利抑制液泡 Na(+)/H(+)反向转运蛋白，从而干扰了叶片的 Na(+)积累，降低了根对 Na(+)的摄取和 Na(+)从茎向叶的转运，从而导致盐胁迫下蒺藜木的生长受到抑制。
