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Single channel K+ currents from HeLa cells.

R Sauvé·G Roy·D Payet
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Abstract

The extracellular patch-clamp technique was used in order to investigate the presence of ionic channels in HeLa cells, a well-known cultured cell type obtained from an epidermoid carcinoma of the cervix. Under Gigohm-seal conditions, discrete current jumps could be observed with patch electrodes containing KCl. These channels were found to be mainly permeable to K+ and showed multiple levels of conductance. From single-channel I-V curve measurements, a strong rectification effect, characterized by a large inward and no detectable outward current, was observed. For negative membrane potentials (0 to -90 mV), the measured current-voltage relationship was found to be mostly linear, corresponding to a single-channel conductance of 40 pS. An analysis of some selected time records has revealed in addition that the probability of the channel to be in the open state was a function of the KCl concentration in the patch pipette.

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Electric ConductivityHeLa CellsHumansIon ChannelsMembrane PotentialsPotassiumPotassium ChlorideJournal ArticleResearch Support, Non-U.S. Gov't

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R Sauvé, G Roy, D Payet. 1983. Single channel K+ currents from HeLa cells.. https://doi.org/10.1007/bf01870593

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