Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2005-9-15
pubmed:abstractText
Transgenic mice overexpressing the inflammatory cytokine TNF-alpha in the heart develop a progressive heart failure syndrome characterized by biventricular dilatation, decreased ejection fraction, decreased survival compared with non-transgenic littermates, and earlier pathology in males. TNF-alpha mice (TNF1.6) develop atrial arrhythmias on ambulatory telemetry monitoring that worsen with age and are more severe in males. We performed in vivo electrophysiological testing in transgenic and control mice, ex vivo optical mapping of voltage in the atria of isolated perfused TNF1.6 hearts, and in vitro studies on isolated atrial muscle and cells to study the mechanisms that lead to the spontaneous arrhythmias. Programmed stimulation induces atrial arrhythmias (n = 8/32) in TNF1.6 but not in control mice (n = 0/37), with a higher inducibility in males. In the isolated perfused hearts, programmed stimulation with single extra beats elicits reentrant atrial arrhythmias (n = 6/6) in TNF1.6 but not control hearts due to slow heterogeneous conduction of the premature beats. Lowering extracellular Ca(2+) normalizes conduction and prevents the arrhythmias. Atrial muscle and cells from TNF1.6 compared with control mice exhibit increased collagen deposition, decreased contractile function, and abnormal systolic and diastolic Ca(2+) handling. Thus abnormalities in action potential propagation and Ca(2+) handling contribute to the initiation of atrial arrhythmias in this mouse model of heart failure.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0363-6135
pubmed:author
pubmed:issnType
Print
pubmed:volume
289
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
H1456-67
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed-meshheading:15923312-Action Potentials, pubmed-meshheading:15923312-Age Factors, pubmed-meshheading:15923312-Animals, pubmed-meshheading:15923312-Atrial Fibrillation, pubmed-meshheading:15923312-Calcium, pubmed-meshheading:15923312-Cardiomyopathies, pubmed-meshheading:15923312-Collagen, pubmed-meshheading:15923312-Disease Models, Animal, pubmed-meshheading:15923312-Electrocardiography, pubmed-meshheading:15923312-Female, pubmed-meshheading:15923312-Fibrosis, pubmed-meshheading:15923312-Gene Expression, pubmed-meshheading:15923312-Heart Atria, pubmed-meshheading:15923312-Heart Failure, pubmed-meshheading:15923312-Heart Rate, pubmed-meshheading:15923312-Male, pubmed-meshheading:15923312-Mice, pubmed-meshheading:15923312-Mice, Transgenic, pubmed-meshheading:15923312-Myocardial Contraction, pubmed-meshheading:15923312-Sex Characteristics, pubmed-meshheading:15923312-Tumor Necrosis Factor-alpha
pubmed:year
2005
pubmed:articleTitle
Atrial contractile dysfunction, fibrosis, and arrhythmias in a mouse model of cardiomyopathy secondary to cardiac-specific overexpression of tumor necrosis factor-{alpha}.
pubmed:affiliation
Cardiovascular Institute, University of Pittsburgh, 200 Lothrop St., Scaife S572, Pittsburgh, PA 15213, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural