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Updated: May 25, 2026
15:28
Mutagenesis and Functional Analysis of Ion Channels Heterologously Expressed in Mammalian Cells
Published on: October 1, 2010
Modeling ion channels in the gigaseal.
Chilman Bae1, Vladislav Markin, Thomas Suchyna
1Department of Physiology and Biophysics, State University of New York, Buffalo, New York, USA.
Biophysical Journal
|January 21, 2012
Summary
Ion channels in the gigaseal can affect patch-clamp electrophysiology measurements. Mathematical modeling reveals their properties and impact on seal resistance and current measurements.
Area of Science:
- Biophysics
- Electrophysiology
Background:
- Gigaseal formation is critical for patch-clamp electrophysiology.
- Ion channels within the seal (rim channels) can influence recorded currents.
Purpose of the Study:
- To mathematically model the properties of ion channels in the gigaseal.
- To investigate their impact on seal resistance and measured currents.
Main Methods:
- Developed a 2D cable model of the seal, including ion depletion/accumulation.
- Modeled ohmic channels with concentration-dependent conductance.
- Used fluorescent dyes (Alexa 488, FM1-43) to characterize the seal.
Main Results:
- High-resistance seals require seal media conductivity <10% of bath conductivity.
- Stimulus voltage attenuates along the seal.
- Seal channels can generate currents comparable to dome channels, albeit with slower kinetics due to membrane capacitance.
Conclusions:
- Rim channels contribute to measured currents in patch-clamp electrophysiology.
- Understanding seal properties is crucial for accurate electrophysiological recordings.
- Uniform channel distribution leads to dome channels dominating patch currents.
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