Ca2+ signaling in porcine duodenal glands by muscarinic receptor activation

Citation
H. Teraoka et al., Ca2+ signaling in porcine duodenal glands by muscarinic receptor activation, AM J P-GAST, 280(4), 2001, pp. G729-G737
Citations number
43
Language
INGLESE
art.tipo
Article
Categorie Soggetti
da verificare
Journal title
AMERICAN JOURNAL OF PHYSIOLOGY-GASTROINTESTINAL AND LIVER PHYSIOLOGY
ISSN journal
0193-1857 → ACNP
Volume
280
Issue
4
Year of publication
2001
Pages
G729 - G737
Database
ISI
SICI code
0193-1857(200104)280:4<G729:CSIPDG>2.0.ZU;2-E
Abstract
The duodenal glands have been thought to play an important role in defense against proximal duodenal ulcer; however, the secretory mechanisms of these glands remain to be determined. In isolated duodenal acinar cells of the p ig, we investigated the effects of ACh on intracellular Ca2+ concentration ([ Ca2+](i)) and on membrane currents with fura 2 fluorometry and the patch clamp technique. ACh caused a transient increase in [Ca2+](i), and the inc rease was markedly inhibited by atropine or 4-diphenylacetoxy-N-methylpiper idine methiodide but not by hexamethonium, pirenzepine, or methoctramine. T he expression of mRNA for the M-3 subtype far exceeded that for either M-1 or M-2 as revealed by real-time quantitative PCR and in situ hybridization. The rise in [Ca2+](i) evoked by ACh was largely inhibited by thapsigargin but slightly affected by extracellular Ca2+ deprivation. Caffeine had no ef fect on [Ca2+](i). ACh elicited Ca2+-dependent K+ currents, a finding simil ar to the response to inositol 1,4,5,-trisphosphate applied intracellularly . These results suggest the presence of M-3 receptors linked to Ca2+ releas e in porcine duodenal glands.