颈动脉体球细胞的细胞内钾活性、钾平衡电位和膜电位。

Intracellular potassium activity, potassium equilibrium potential and membrane potential of carotid body glomus cells.

作者信息

Oyama Y, Walker J L, Eyzaguirre C

出版信息

Brain Res. 1986 Sep 3;381(2):405-8. doi: 10.1016/0006-8993(86)90100-9.

Abstract

The intracellular potassium activity (ai(K)) of glomus cells in isolated rabbit carotid bodies was measured with potassium ion selective microelectrodes (K+ electrodes). The measurements yielded a mean ai(K) value of 33.0 mM in Hepes-buffered Tyrode's solution equilibrated with 100% O2. This value is significantly higher than that predicted by assuming that K+ ions are passively distributed across the membrane of glomus cells. The relationship between the membrane potential (EM) and the equilibrium potential of K+ ions (EK) at various extracellular potassium activities (ao(K] suggests that K+ ions are not involved in the maintenance of the carotid body glomus cell EM.

摘要

采用钾离子选择性微电极（K⁺电极）测量了离体兔颈动脉体球细胞的细胞内钾活性（ai(K)）。在与100% O₂平衡的Hepes缓冲台氏液中进行测量，得到的ai(K)平均值为33.0 mM。该值显著高于假设K⁺离子在球细胞膜上被动分布所预测的值。在不同细胞外钾活性（ao(K)）下，膜电位（EM）与K⁺离子平衡电位（EK）之间的关系表明，K⁺离子不参与颈动脉体球细胞膜电位的维持。