Impaled Valonia ventricosa
Impaled Valonia ventricosa
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DOI：
10.1085/jgp.14.1.139
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发表时间：
1930-09-01
影响因子：
3.8
通讯作者：
Blinks, LR
中科院分区：
文献类型：
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作者：
Blinks, LR
在许多新采集的Valonia ventricosa细胞中，原生质对直流电的表观电阻随测量时所施加的电位值而变化。进一步表明，在这种细胞中，单层原生质的表观电阻也取决于电流的方向，当所施加的电位增加以向外携带正电流穿过它时，但在第一次增加100 Inv时大幅上升。这些方向效应是在细胞中研究的，其中一端的接触区已被氯仿杀死。因此，它们仅限于完整端不受扩散影响的时间。氯仿的锡永，或者另一端的死亡。最多十五分钟到半个小时。为了大大延长在单层原生质上进行这些测量的时间，并避免有毒物质的影响，用刺入细玻璃毛细管上的V.ventricosa细胞进行了一系列电阻测量。通过这些通道，电流被引入（或引出）液泡，只穿过原生质一次，进入（或离开）周围的海水。人们认识到，这种方法的优点与毛细管插入细胞可能造成的损伤相平衡。已经注意到 *，已经到达
In many freshly gathered ceils of Valonia ventricosa the apparent resistance of the protoplasm to direct current varies with the value of the potential applied to measure it. 1 It was further shown 1 that the apparent resistance of a single layer of protoplasm in such cells depends also upon the direction of the current, falling somewhat when the applied potential is increased to carry the positive current outward across it, but rising greatly during the first increase of 100 Inv. in the opposite (inward) sense.These directional effects were studied in cells in which the contactregion at one end had been killed with chloroform. They were therefore limited to the time during which the intact end remained uninfluenced by the diffu. sion of chloroform, or by the death of the other end. This was at most 15 minutes to half an hour. In order to extend greatly the time of these measurements across a single layer of protoplasm, and to avoid the influence of toxic agents, a series of resistance measurements was made with V. ventricosa cells impaled upon fine glass capillaries. Through these the current was led into (or out of) the vacuole, and passed but once across the protoplasm to (or from) the surrounding sea water. It is recognized that the advantages of this method are balanced by the possible injury inflicted by the insertion of a capillary into the cell. It has already been noted* that cells which have reached the