Document Detail


Spontaneous and inducible ventricular arrhythmias after myocardial infarction in mice.
MedLine Citation:
PMID:  15081472     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
INTRODUCTION: Remodeling of gap junctions has been implicated in development of ventricular arrhythmias following myocardial infarction (MI) but the specific contribution of reduced electrical coupling is not known. We addressed this question using hearts from mice heterozygous for a connexin43 null allele (Cx43(+/-)). METHODS: To determine whether Cx43-deficient mice exhibit increased spontaneous ventricular arrhythmias in the setting of chronic ischemic heart disease, radiofrequency transmitters were implanted in wild-type and Cx43(+/-) mice 2 days or 9 weeks after left anterior descending coronary artery ligation or sham operations. ECGs were recorded from unanesthetized, unrestrained mice 1 and 10 weeks after MI. Isolated, perfused hearts excised 1 and 10 weeks after MI were subjected to programmed electrical stimulation to induce arrhythmias. RESULTS AND CONCLUSIONS: Hearts with infarcts exhibited more spontaneous and inducible arrhythmias, but there was no significant difference between wild-type and Cx43-deficient mice. Fewer hearts exhibited spontaneous ventricular tachycardia (VT) in vivo than were inducible in vitro, suggesting that structural and functional substrates for inducible VT in isolated hearts may not be sufficient for initiation and maintenance of sustained VT in vivo. Previous studies have shown that Cx43-deficient mice exhibit more VT than wild-type mice during acute regional ischemia. Mice with MI exhibit increased arrhythmias. However, reduced coupling in Cx43-deficient mice does not significantly enhance spontaneous or inducible VT after MI.
Authors:
Tetsuo Betsuyaku; Shigeto Kanno; Deborah L Lerner; Richard B Schuessler; Jeffrey E Saffitz; Kathryn A Yamada
Publication Detail:
Type:  In Vitro; Journal Article; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  Cardiovascular pathology : the official journal of the Society for Cardiovascular Pathology     Volume:  13     ISSN:  1054-8807     ISO Abbreviation:  Cardiovasc. Pathol.     Publication Date:    2004 May-Jun
Date Detail:
Created Date:  2004-04-14     Completed Date:  2004-12-23     Revised Date:  2007-11-14    
Medline Journal Info:
Nlm Unique ID:  9212060     Medline TA:  Cardiovasc Pathol     Country:  United States    
Other Details:
Languages:  eng     Pagination:  156-64     Citation Subset:  IM    
Affiliation:
Department of Medicine (Cardiovascular Division), Washington University School of Medicine, St. Louis, MO 63110, USA.
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MeSH Terms
Descriptor/Qualifier:
Animals
Connexin 43 / deficiency*,  genetics
Electric Stimulation
Electrocardiography
Gap Junctions / physiology
Mice
Myocardial Infarction / complications,  physiopathology*
Organ Culture Techniques
Tachycardia, Ventricular / etiology,  physiopathology*
Grant Support
ID/Acronym/Agency:
HL-50598/HL/NHLBI NIH HHS; HL-58507/HL/NHLBI NIH HHS; HL-66350/HL/NHLBI NIH HHS
Chemical
Reg. No./Substance:
0/Connexin 43

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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