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Updated: Jul 25, 2026
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Patch-clamp Capacitance Measurements and Ca2+ Imaging at Single Nerve Terminals in Retinal Slices
Published on: January 19, 2012
System for dynamic measurements of membrane capacitance in intact epithelial monolayers
C A Bertrand1, D M Durand, G M Saidel
1Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, Ohio 44106 USA.
Biophysical Journal
|November 25, 1998
Summary
A new impedance measurement system accurately quantifies epithelial monolayer membrane capacitance, enabling dynamic exocytosis studies. This method precisely measures mucin exocytosis in HT29-CI.16E cells.
Area of Science:
- Epithelial physiology
- Biophysics
- Cell biology
Background:
- Dynamic exocytosis measurements in intact epithelial monolayers are challenging.
- Accurate quantification of membrane capacitance is crucial for understanding cellular transport.
Purpose of the Study:
- To develop and validate a novel impedance measurement system for dynamic exocytosis studies in epithelial monolayers.
- To accurately estimate total membrane capacitance and individual membrane parameters.
Main Methods:
- Designed an impedance measurement and analysis system using a transepithelial electrophysiology clamp.
- Employed a weighted, nonlinear, least-squares algorithm to estimate monolayer impedance coefficients.
- Validated the system using circuit simulations, Monte Carlo simulations, and analog model circuits.
Main Results:
- The system estimates total membrane capacitance with +/-1% accuracy (99% confidence).
- Individual membrane parameters are calculated with results frequently within +/-20% of true values.
- Quantified capacitance changes during purinergically stimulated mucin exocytosis in HT29-CI.16E cells.
Conclusions:
- The developed system provides accurate and dynamic measurements of epithelial monolayer capacitance.
- This technology facilitates the study of exocytosis and other membrane trafficking events.
- Enables precise quantification of cellular processes in epithelial models.
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