Linked Life Data

12491798

Source:http://linkedlifedata.com/resource/pubmed/id/12491798

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2002-12-20
pubmed:abstractText
beta-Adrenoceptor subtypes which mediate relaxation of guinea-pig gastrointestinal smooth muscles in response to catecholamines ((-)-isoprenaline, (-)-noradrenaline and (-)-adrenaline) and beta 3-adrenoceptor agonists (BRL37344 and (+/-)-CGP12177A) are predominantly beta 3-adrenoceptors. Although cAMP-PKA system is thought to play a substantial role in the smooth muscle relaxation mediated via beta 1- and beta 2-adrenoceptors, there is little information on the role of cAMP in beta 3-adrenoceptor-meidated relaxation. The present study was carried out to elucidate the role of cAMP in beta 3-adrenoceptor-meidated relaxation of guinea-pig gastric fundus smooth muscle. Furthermore, possible contribution of two types of K+ (voltage-dependent and Ca(2+)-activated K+, BKCa; voltage-dependent, Kv) channels was also examined pharmaco-mechanically. In gastric fundus smooth muscle, catecholamines and beta 3-adrenoceptor agonists elicited potent relaxations in the presence of beta 1- and beta 2-adrenoceptor antagonists. All of these relaxations were not diminished by an adenylate cyclase inhibitor, SQ-22,536 (100 microM), which indicates their characteristic of cAMP-independency. SQ-22,536-resistant, beta 3-adrenoceptor-mediated relaxations were strongly attenuated by a Kv channel blocker, 4-aminopyridine (3 mM), but not by iberiotoxin (100 nM), a selective blocker of BKCa channel. The present results indicate that 4-aminopyridine-sensitive Kv channels play a primary role in cAMP-independent relaxation of guinea-pig gastric fundus smooth muscle in response to the stimulations of beta 3-adrenoceptors.
pubmed:language
jpn
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0015-5691
pubmed:author
pubmed:issnType
Print
pubmed:volume
120
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
109P-111P
pubmed:dateRevised
2011-7-27
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
[Beta 3-adrenoceptor-mediated relaxation of guinea-pig gastric funds smooth muscle: cAMP-independent characteristics and a primary role of 4-aminopyridine-sensitive voltage-dependent K+ (Kv) channels].
pubmed:affiliation
Department of Chemical Pharmacology, Toho University School of Pharmaceutical Sciences, 2-2-1 Miyama, Funabashi-City, Chiba 274-8510, Japan.
pubmed:publicationType
Journal Article, In Vitro, English Abstract