Measurement of intracellular potassium activity in protoplasts of Acer pseudoplatanus: origin of their electropositivity
Measurement of intracellular potassium activity in protoplasts of Acer pseudoplatanus: origin of their electropositivity
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拟梧桐原生质体细胞内钾活性的测量：其电正性的起源
DOI：
10.1111/j.1399-3054.1983.tb00900.x
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发表时间：
1983
期刊：
影响因子：
--
通讯作者：
R. Heller
中科院分区：
文献类型：
--
作者：
D. Cornel;C. Grignon;J. Rona;R. Heller
研究了悬铃木原生质体的膜电阻、膜电位和细胞内K+活性。使用微电极。质膜在原生质体加工过程中似乎受到损伤，因此几乎完全去极化。原生质体的正极性是其液泡膜的一个特性。一般稀释培养基的渗透压休克引起原生质体轻微的正极化，这可能是细胞离子含量稀释的结果。细胞外钾的快速稀释通过K+的大量流出产生相同的效果，这改变了浓度梯度，从而加重了正电性。一般来说，某些冲击状态会导致这种极化。这些结果，特别是内部钾活性的发展，有助于理解有时在原生质体中观察到的正极化的最初原因。
Membrane resistances, electrical potentials and intracellular K+ activity have been studied in protoplasts of Acer pseudoplatanus L. using microelectrodes. The plasmalemma appears to be damaged during protoplast processing, so that it is almost completely depolarized. The positive polarization of the protoplasts is a property of their tonoplast. The osmotic shock of general dilution of the medium brings about a slight positive polarization of the protoplasts, which probably is the consequence of a dilution of the ionic contents of the cell. A rapid dilution of extracellular potassium produces the same effect by a considerable efflux of K+, which changes the concentration gradient so that electropositivity is accentuated. In general, certain states of shock can cause such polarization. These results, particularly the development of internal potassium activity, help in understanding the initial cause of the positive polarization that is sometimes observed in protoplasts.