Schrempf M, Satter R L, Galston A W
Department of Biology, Yale University, New Haven, Connecticut 06520.
Plant Physiol. 1976 Aug;58(2):190-2. doi: 10.1104/pp.58.2.190.
Transverse sections of Albizzia pulvinules were examined with an electron microprobe to determine ion fluxes associated with turgorcontrolled leaflet movements. K(+) and Cl(-) concentrations are high in the flexor and low in the extensor region of closed pulvini. Both ions migrate out of the flexor and into the extensor during opening as previously described for K(+). The distribution of these elements is significantly correlated in each phase of the rhythmic cycle examined, but only 50 to 60% of the ionic charge of potassium is balanced by chloride. This value increases to 65 to 85% if one considers only the mobile fraction of the potassium.The increase in concentration of both ions in the extensor region precedes the decrease in the flexor, thus indicating that there must be a storage reservoir for K(+) and Cl(-). The inner cortex is suggested as such a reservoir, and plasmodesmata are discussed as a probable pathway for ion movement.
用电子微探针检查了合欢小叶的横切面，以确定与膨压控制的小叶运动相关的离子通量。在闭合叶枕的屈肌区域钾离子（K⁺）和氯离子（Cl⁻）浓度较高，而在伸肌区域浓度较低。如先前对钾离子所描述的那样，在叶片张开期间，这两种离子都从屈肌区域移出并进入伸肌区域。在所研究的节律周期的每个阶段，这些元素的分布都显著相关，但只有50%至60%的钾离子电荷由氯离子平衡。如果仅考虑钾离子的可移动部分，这个值会增加到65%至85%。伸肌区域中两种离子浓度的增加先于屈肌区域中离子浓度的降低，因此表明一定存在一个钾离子和氯离子的储存库。有人认为内皮层就是这样一个储存库，并讨论了胞间连丝作为离子移动的可能途径。
