| Acetylcholine receptor channels on adult mouse skeletal muscle are functionally identical in synaptic and nonsynaptic membrane. | |
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MedLine Citation:
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PMID: 2436235 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
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It has been proposed that acetylcholine receptor channels exhibit a functionally distinct "junctional" form at the region of synaptic contact between nerve and muscle. As a direct test of this idea, we compared acetylcholine-activated single-channel currents from the synaptic membrane to those obtained from nonsynaptic sites on freshly dissociated adult mouse toe muscle. We observed, at locations along the entire length of the cell, openings by a channel with a high conductance (70 pS) and brief open time (approximately 2 msec), characteristic of the classical "junctional type" of acetylcholine receptor. In 8 out of 10 synaptic and in 9 out of 19 nonsynaptic recordings, we also observed infrequent openings by a low-conductance (45-pS) channel traditionally associated only with nonsynaptic regions. In these recordings the low-conductance acetylcholine receptor channel averaged only 3% of the total channel openings. Comparisons of synaptic and nonsynaptic patches indicated no trend toward an increased proportion of low-conductance channel openings with increased distance from the synapse. These findings support the view that the functional properties of the acetylcholine receptor channel do not depend on proximity to the synapse in innervated mouse skeletal muscle. |
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Authors:
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P Brehm; R Kullberg |
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Publication Detail:
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Type: Journal Article; Research Support, U.S. Gov't, P.H.S. |
Journal Detail:
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Title: Proceedings of the National Academy of Sciences of the United States of America Volume: 84 ISSN: 0027-8424 ISO Abbreviation: Proc. Natl. Acad. Sci. U.S.A. Publication Date: 1987 Apr |
Date Detail:
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Created Date: 1987-05-15 Completed Date: 1987-05-15 Revised Date: 2009-11-18 |
Medline Journal Info:
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Nlm Unique ID: 7505876 Medline TA: Proc Natl Acad Sci U S A Country: UNITED STATES |
Other Details:
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Languages: eng Pagination: 2550-4 Citation Subset: IM |
Export Citation:
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| MeSH Terms | |
Descriptor/Qualifier:
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Acetylcholine
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pharmacology Animals Cell Membrane / drug effects, physiology Ion Channels / physiology* Mice Mice, Inbred C57BL Muscles / innervation*, physiology Receptors, Cholinergic / physiology* Synaptic Membranes / drug effects, physiology* |
| Grant Support | |
ID/Acronym/Agency:
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NS17875/NS/NINDS NIH HHS; NS18205/NS/NINDS NIH HHS |
| Chemical | |
Reg. No./Substance:
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0/Ion Channels; 0/Receptors, Cholinergic; 51-84-3/Acetylcholine |
| Comments/Corrections | |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
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