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Updated: Jul 30, 2026
10:04
Local Application of Drugs to Study Nicotinic Acetylcholine Receptor Function in Mouse Brain Slices
Published on: October 29, 2012
Evidence for cooperativity between nicotinic acetylcholine receptors in patch clamp records
A M Keleshian1, R O Edeson, G J Liu
1Department of Physiology, State University of New York at Buffalo, Buffalo, New York 14214 USA. amk7@acsu.buffalo.edu
Biophysical Journal
|January 5, 2000
Summary
Ion channels in cell membranes may not open independently. This study suggests positive cooperativity between nicotinic acetylcholine receptors in embryonic chick myotubes, where one channel opening increases the likelihood of a neighbor opening.
Area of Science:
- Neuroscience
- Biophysics
- Molecular Biology
Background:
- Ion channels in cell membranes are often assumed to gate independently.
- Patch clamp studies are crucial for understanding ion channel kinetics.
Purpose of the Study:
- To investigate potential non-independent gating of nicotinic acetylcholine receptors.
- To determine if positive cooperativity exists between ion channels in cell membranes.
Main Methods:
- Utilized patch clamp electrophysiology on embryonic chick myotubes.
- Applied a five-state continuous-time Markov process to model receptor behavior.
- Developed a model incorporating cooperativity through instantaneous transition rate changes.
Main Results:
- Observed probabilities of concurrent channel openings deviating from binomial distribution.
- Found evidence suggesting positive cooperativity between nicotinic receptors.
- Calculated conditional open and closed sojourn time density functions.
Conclusions:
- Individual acetylcholine receptors appear kinetically identical.
- The open state of one ion channel positively influences the opening probability of adjacent channels.
- Suggests cooperative gating mechanisms in cell membrane ion channels.
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