Linked Life Data

1968362

Source:http://linkedlifedata.com/resource/pubmed/id/1968362

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1990-4-6
pubmed:abstractText
We have investigated the actions of acetylcholine in the absence and presence of the beta-agonist isoproterenol in cardiac Purkinje fibers. beta-Agonists, like isoproterenol, increase the magnitude of the pacemaker current (If) in cardiac myocytes by shifting its activation voltage more positive on the voltage axis. We find that acetylcholine has no effect on If in the absence of isoproterenol. However, if If is first increased by beta-agonist stimulation, acetylcholine can then return If to control levels. This effect on If is exerted through muscarinic receptors since atropine prevents this action of acetylcholine. Functionally, this action of acetylcholine can guarantee the maintenance of ventricular pacemakers when there is high parasympathetic tone but can also prevent extra ventricular beats when sympathetic and parasympathetic tone are both high.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0009-7330
pubmed:author
pubmed:issnType
Print
pubmed:volume
66
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
633-6
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Acetylcholine reverses effects of beta-agonists on pacemaker current in canine cardiac Purkinje fibers but has no direct action. A difference between primary and secondary pacemakers.
pubmed:affiliation
Department of Physiology and Biophysics, SUNY, Stony Brook 11794-8661.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.