ISSN:
1432-1912
Keywords:
Antimuscarinics
;
Gastric acid secretion
;
Mouse isolated stomach
;
Telenzepine
;
McN-A-343
;
Histamine release
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Summary (1) In the lumen-perfused mouse stomach in vitro, potential sites of gastric antisecretory action of the muscarine M1-receptor antagonist telenzepine were investigated. Acid secretion was stimulated by the muscarinic agonist McN-A-343 (1–1000 μmol/l). Neither basal nor McN-A343-stimulated acid secretion was affected by 1 μmol/l TTX indicating that neuronal structures were probably not involved. (2) Acid secretion stimulated by 10 μmol/l McNA-343 was inhibited by telenzepine (0.1-1.4 μmol/l) and cimetidine (10–140 μmol/l). Neither of the antagonists affected basal acid secretion. TTX had no inhibitory influence on the antagonist effect of telenzepine and cimetidine. (3) Compound 48/80 (100 pmol/l), which depletes histamine stores, initially mimicked but subsequently prevented the effect of McN-A-343. Prenylamine (50 μmol/l), which prevents histamine release, also abolished the secretagogue effect of subsequently administered McN-A-343. (4) Up to concentrations greater than 100 μmol/l, McN-A-343 did not stimulate acid production in rabbit isolated fundic glands and guinea-pig isolated parietal cells. Thus, parietal cells are not directly stimulated by McN-A-343. (5) Based on the site of action of the agonist McN-A-343 in the mouse isolated stomach and its failure to stimulate parietal cells from different species directly, it is concluded that telenzepine blocks, in the mouse isolated stomach, muscarine receptors located on paracrine cells to reduce endogenous histamine release.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00169209
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