REGIONAL VARIATIONS IN RESPONSE OF CAT ESOPHAGEAL MUSCLE TO STIMULATION WITH DRUGS
We sought to explain differences in the regional responses of the esophagus to swallowing in terms of qualitative and quantitative differences in responses to drugs. Isometric contractions of muscle strips in vitro, in response to acetylcholine, carbachol, methacholine and norepinephrine, in concent...
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Published in | The Journal of pharmacology and experimental therapeutics Vol. 161; no. 1; pp. 55 - 58 |
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Main Authors | , |
Format | Journal Article |
Language | English |
Published |
United States
American Society for Pharmacology and Experimental Therapeutics
01.05.1968
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Subjects | |
Online Access | Get full text |
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Summary: | We sought to explain differences in the regional responses of the esophagus to swallowing in terms of qualitative and quantitative
differences in responses to drugs. Isometric contractions of muscle strips in vitro, in response to acetylcholine, carbachol, methacholine and norepinephrine, in concentrations from 10 -8 to 10 -5 g/ml, were measured to determine dose-response curves to these four drugs. Transverse strips of esophageal wall at various
levels of the distal 12 cm of the cat esophagus were compared. There were no qualitative differences between responses of
strips from the distal and midesophagus. The most proximal strips, from 10 to 12 cm above the phrenoesophageal ligament, exerted
less tension than more distal strips at equal concentrations of all four drugs. These results fail to demonstrate a qualitative
difference between sphincteric and nonsphincteric muscle. The diminished responsiveness of the most proximal level indicates
that striated muscle, which predominates over smooth muscle at this level, is not stimulated under these conditions. |
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Bibliography: | ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0022-3565 1521-0103 |