Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
1996-2-20
pubmed:abstractText
In the human isolated myocardium, acetylcholine (10(-9) to 10(-3) M) elicited a biphasic inotropic effect (a decrease in the lower and an increase in the higher concentration range) in atrial and a positive inotropic effect in ventricular trabeculae. However, under conditions of raised contractility achieved by exposure to noradrenaline (10(-5) M), only negative inotropic effects were observed in both atria and ventricles. Atropine (10(-6) M), but not propranolol (10(-6) M), antagonized both positive and negative inotropic effects of acetylcholine, thus showing that the responses were mediated by muscarinic acetylcholine receptors. The use of subtype selective muscarinic receptor antagonists (10(-7) to 10(-5) M), pirenzepine (M1 > M3 > M2), AF-DX 116 (11-([2-[(diethylamino)-methyl]-1-piperidyl]acetyl)-5,11-dihydro-6H- pyridol[2,3-b][1,4]benzodiazepine-6-one base; M2 > M1 > M3) and HHSiD (p-fluorohexahydro-siladifenidol hydrochloride; M3 > or = M1 >> M2) revealed that the negative inotropic effect of acetylcholine in atrial as well as the positive inotropic effect in ventricular trabeculae were best antagonized by AF-DX 116 and not by pirenzepine, suggesting the involvement of the muscarinic M2 receptor subtype, possibly linked to different second messenger systems. On the other hand, the positive inotropic effect of acetylcholine (10(-6) to 10(-3) M) in the atrial tissue, observed only in preparation with depressed contractility, was not effectively antagonized by either AF-DX 116 or HHSiD, but was significantly reduced by pirenzepine. (ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0014-2999
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
284
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
119-27
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:8549614-(4-(m-Chlorophenylcarbamoyloxy)-2-butynyl)trimethylammonium..., pubmed-meshheading:8549614-Acetylcholine, pubmed-meshheading:8549614-Adolescent, pubmed-meshheading:8549614-Adult, pubmed-meshheading:8549614-Child, pubmed-meshheading:8549614-Child, Preschool, pubmed-meshheading:8549614-Female, pubmed-meshheading:8549614-Heart, pubmed-meshheading:8549614-Heart Atria, pubmed-meshheading:8549614-Heart Ventricles, pubmed-meshheading:8549614-Humans, pubmed-meshheading:8549614-Male, pubmed-meshheading:8549614-Middle Aged, pubmed-meshheading:8549614-Muscarinic Agonists, pubmed-meshheading:8549614-Muscarinic Antagonists, pubmed-meshheading:8549614-Myocardial Contraction, pubmed-meshheading:8549614-Norepinephrine, pubmed-meshheading:8549614-Receptors, Muscarinic, pubmed-meshheading:8549614-Sympathomimetics
pubmed:year
1995
pubmed:articleTitle
Characterization of the positive and negative inotropic effects of acetylcholine in the human myocardium.
pubmed:affiliation
Department of Pharmacology, Faculty of Medicine and Health Sciences, Erasmus University Rotterdam, Netherlands.
pubmed:publicationType
Journal Article, In Vitro