Changes in Membrane Impedance associated with a Cortical Contraction in the Egg of Xenopus laevis
Changes in Membrane Impedance associated with a Cortical Contraction in the Egg of Xenopus laevis
复制标题
非洲爪蟾卵中与皮质收缩相关的膜阻抗变化
DOI：
10.1038/217098a0
复制
发表时间：
1968
期刊：
影响因子：
64.8
通讯作者：
J. F. Palmer
中科院分区：
文献类型：
--
作者：
D. Gingell;J. F. Palmer
最近人们注意到细胞膜作为外部刺激传感器的概念，通过改变表面电位来介导环境效应器和细胞质反应（参考文献 1 和 2，以及我们自己正在准备的结果）。由于外部离子强度的变化、聚离子的吸附或细胞表面的接近而引起的静电表面电位的变化，导致膜电位分布的改变，可能导致细胞质反应1。膜场的变化可能会影响膜大分子的构象，导致新基团在细胞质界面处出现。或者，膜渗透性的变化可能跟随构象变化，或者可能在构象变化不存在时发生。这些机制中的任何一种都可以为细胞质提供有关其可能采取相应行动的外部环境的信息。 Changeux 和他的同事 3,4 设想的膜中协同现象的可能性在这方面引起了极大的兴趣，特别是因为协同变化的刺激可能是膜静电场的变化 5。
ATTENTION has recently been drawn to the concept of the cell membrane as a transducer of external stimuli, mediating between environmental effectors and cyto-plasmic responses by altering the surface potential (refs. 1 and 2, and our own results which are in preparation). Alteration of the potential profile through the membrane, resulting from a change in electrostatic surface potential caused by changes in external ionic strength, adsorption of polyions or the close approach of cell surfaces, could lead to cytoplasmic reactions1. Changes in membrane field might affect the conformation of membrane macro-molecules, leading to the presentation of new groups at the cytoplasmic interface. Alternatively, changes in permeability of the membrane might follow conformational changes, or else might occur in their absence. Any of these mechanisms could provide the cytoplasm with information about the external environment on which it might act accordingly. The possibility of co-operative phenomena in membranes, envisaged by Changeux and his colleagues3,4, is of great interest in this respect, especially because the stimulus for co-operative change might be a change in membrane electrostatic field5.