Biophysics Department, University of California at Los Angeles, Los Angeles, California 90024.
Plant Physiol. 1969 Aug;44(8):1101-7. doi: 10.1104/pp.44.8.1101.
The efflux of K(+) from the pulvinar cells of Mimosa pudica was shown to increase substantially during the seismonastic reaction. This result is shown to indicate a decrease in sigma (reflection coefficient) of pulvinar cell membrane for potassium salts which could account for the pulvinar cell turgor decrease during the seismonastic reaction.Membrane potentials and concentrations of Ca(2+), K(+), Cl(-), S, and P were measured in the top and bottom halves of pulvini. Pulvinar cells showed a large negative membrane potential, cell vacuole relative to external solution, but no significant difference in membrane potential could be detected between upper and lower pulvinar cells. A large difference in K(+) and Cl(-) concentration between top and bottom pulvinar halves was evident in reactive pulvini but not in unreactive pulvini. The effect of K(+) concentration on plant growth and leaf reactivity was also investigated.
含羞草叶褥细胞中的 K(+)外流，在感震反应过程中明显增加。这一结果表明，含羞草叶褥细胞膜对钾盐的西格玛（反射系数）降低，这可以解释感震反应过程中叶褥细胞膨压的下降。测量了叶褥顶部和底部的膜电位和 Ca(2+)、K(+)、Cl(-)、S 和 P 的浓度。叶褥细胞表现出相对于外部溶液的大的负膜电位，但在上部和下部叶褥细胞之间没有检测到膜电位的显著差异。在反应性叶褥中，上部和下部叶褥之间的 K(+)和 Cl(-)浓度存在明显差异，但在非反应性叶褥中则没有。还研究了 K(+)浓度对植物生长和叶片反应性的影响。
