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Updated: Aug 8, 2026

In vitro Measurements of Tracheal Constriction Using Mice
Published on: June 25, 2012
Responsiveness and sensitivity to cholinergic agonists and antagonists in bovine isolated bronchial muscle
M G Matera1, M Cazzola, M Constantino
1Institute of Pharmacology and Toxicology, First Faculty of Medicine, University of Naples, Italy.
Abstract:
1. Airways derived from different levels of the lung exhibit a difference in the reactivity and sensitivity to agonists. We have evaluated the effect of acetylcholine and cholinergic selective (pirenzepine, gallamine and 4-dipherylacetoxymethyl piperidine [4-DAMP]) and non-selective (atropine) antagonists on bovine proximal and distal smooth muscle preparations. 2. The distal preparations are more sensitive to acetylcholine than proximal bronchi. The relaxant effect of three selective antagonists on the distal and proximal tissues was the same when the results for each drug were compared. 3. Atropine and 4-DAMP were more potent than pirenzepine and gallamine in relaxing both proximal and distal bovine smooth muscle preparations. 4. These data suggest that the muscarinic sites on the smooth muscle of bovine airways are of the M3 subtype.
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