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Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1971 Sep;68(9):2006–2007. doi: 10.1073/pnas.68.9.2006

Autoinhibition of Acetylcholine Binding to Torpedo Electroplax; A Possible Molecular Mechanism for Desensitization

M E Eldefrawi 1, R D O'Brien 1
PMCID: PMC389336  PMID: 4332243

Abstract

Binding of [3H]acetylcholine (measured by equilibrium dialysis) to a particulate preparation of Torpedo electroplax exhibits autoinhibition at concentrations higher than 1 μM. It is suggested that autoinhibition results from acetylcholine binding to regulatory sites on its receptor macromolecules. This binding causes the change to a new and inactive conformation and rejection of acetylcholine bound to the larger number of active sites. The relationship to the physiological phenomenon of desensitization is discussed.

Keywords: equilibrium dialysis, acetylcholinesterase, receptors

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2006

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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