Transmembrane Potential Measurements of Cells of Higher Plants as Related to Salt Uptake
Transmembrane Potential Measurements of Cells of Higher Plants as Related to Salt Uptake
复制标题
高等植物细胞与盐吸收相关的跨膜电位测量
作者：
B. Etherton;N. Higinbotham
首次在几种作物的细胞中测量了细胞内部和外部溶液之间的电位差（1）。燕麦、豌豆和玉米幼苗组织的细胞内部相对于浸泡组织的0.1毫摩尔KCl/升的外部溶液都具有约-80至-115 mV的电位。燕麦胚芽鞘的电位差随外源KCl浓度的变化而变化，2，4-二硝基苯酚可抑制燕麦胚芽鞘的电位差。电位差发生在细胞质层和外部之间;液泡的电位似乎与细胞质的电位没有显著差异。显然，在植物细胞中，相对较大的阳离子积累率可以通过这种大的电势来解释，而不需要化学阳离子运输方案。
Measurements of the difference in electropotential between the interior of the cell and the external solution have been made for the first time in cells of several crop plants (1). The interiors of cells of Avena, Pisum, and Zea seedling tissues all have potentials of about —80 to —115 mv relative to that of an external solution of 0.1 mmole of KC1 per liter, bathing the tissue. The potential difference of Avena coleoptiles varies with the concentration of external KC1 and is depressed by 2,4-dinitrophenol. The potential difference occurs between the cytoplasmic layer and the exterior; the potential of the vacuole does not appear to be significantly different from that of the cytoplasm. Obviously a relatively large cation accumulation ratio could be accounted for in plant cells by this large potential without invoking a chemical cation transport scheme.