ID 113025
Author
Tangsucharit, Panot Okayama University|Khon Kaen University
Takatori, Shingo Okayama University|Matsuyama University
Pakdeechote, Poungrat Khon Kaen University
Kawasaki, Hiromu Okayama University|Matsuyama University
Takayama, Fusako Okayama University
Keywords
Acetylcholine-induced vasodilatation
CGRPergic nerves
Muscarinic receptor subtypes
Rat mesenteric arteries
Content Type
Journal Article
Description
The present study investigated pharmacological characterizations of muscarinic acetylcholine receptor (AChR) subtypes involving ACh-induced endothelium-independent vasodilatation in rat mesenteric arteries. Changes in perfusion pressure to periarterial nerve stimulation and ACh were measured before and after the perfusion of Krebs solution containing muscarinic receptor antagonists. Distributions of muscarinic AChR subtypes in mesenteric arteries with an intact endothelium were studied using Western blotting. The expression level of M1 and M3 was significantly greater than that of M2. Endothelium removal significantly decreased expression levels of M2 and M3, but not M1. In perfused mesenteric vascular beds with intact endothelium and active tone, exogenous ACh (1, 10, and 100 nmol) produced concentration-dependent and long-lasting vasodilatations. In endothelium-denuded preparations, relaxation to ACh (1 nmol) disappeared, but ACh at 10 and 100 nmol caused long-lasting vasodilatations, which were markedly blocked by the treatment of pirenzepine (M1 antagonist) or 4-DAMP (M1 and M3 antagonist) plus hexamethonium (nicotinic AChR antagonist), but not methoctramine (M2 and M4 antagonist). These results suggest that muscarinic AChR subtypes, mainly M1, distribute throughout the rat mesenteric arteries, and that activation of M1 and/or M3 which may be located on CGRPergic nerves releases CGRP, causing an endothelium-independent vasodilatation.
Journal Title
Journal of Pharmacological Sciences
ISSN
13478613
NCID
AA12022662
Publisher
Japanese Pharmacological Society|Elsevier
Volume
130
Issue
1
Start Page
24
End Page
32
Published Date
2016-01-08
Rights
© 2015 Japanese Pharmacological Society. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
EDB ID
DOI (Published Version)
URL ( Publisher's Version )
FullText File
language
eng
TextVersion
Publisher
departments
Medical Sciences
University Hospital