Skip Navigation

Cardiovascular Research 2001 51(4):681-690; doi:10.1016/S0008-6363(01)00341-8
© 2001 by European Society of Cardiology
This Article
Right arrow Full Text Freely available
Right arrow FREE Full Text (PDF) Freely available
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Eloff, B. C
Right arrow Articles by Rosenbaum, D. S
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Eloff, B. C
Right arrow Articles by Rosenbaum, D. S
Social Bookmarking
 Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

Copyright © 2000, European Society of Cardiology

High resolution optical mapping reveals conduction slowing in connexin43 deficient mice

Benjamin C Eloffa, Deborah L Lernerb, Kathryn A Yamadab, Richard B Schuesslerb, Jeffrey E Saffitzb and David S Rosenbauma,*

aThe Heart and Vascular Research Center and the Department of Biomedical Engineering, MetroHealth Campus, Case Western Reserve University, 2500 MetroHealth Drive, Hamman 322, Cleveland, OH 44109-1998, USA
bThe Departments of Medicine, Pediatrics, Surgery and Pathology, and the Center for Cardiovascular Research, Washington University School of Medicine, St. Louis, MO, USA

* Corresponding author. Tel.: +1-216-778-2005; fax: 1-216-778-4924 drosenbaum{at}metrohealth.org

Analysis of mice with genetically altered expression of cardiac connexins can provide insights into the role of individual gap junction channel proteins in cell-to-cell communication, impulse propagation, and arrhythmias. However, conflicting results have been reported regarding conduction velocity slowing in mice heterozygous for a null mutation in the gene encoding connexin43 (Cx43). Methods: High-resolution optical mapping was used to record action potentials from 256 sites, simultaneously, on the ventricular surface of Langendorff perfused hearts from 15 heterozygous (Cx43+/–) and 8 wildtype (Cx43+/+) mice (controls). A sensitive method for measuring epicardial conduction velocity was developed to minimize confounding influences of subepicardial breakthrough and virtual electrode effects. Results: Epicardial conduction velocity was significantly slower (23 to 35%, P<0.01) in Cx43+/– mice compared to wildtype. There was no change in conduction patterns or anisotropic ratio (Cx43+/– 1.54±0.33; Cx43+/+ 1.57±0.17) suggesting that Cx43 expression was reduced uniformly throughout myocardium. The magnitude of reductions in conduction velocity and Cx43 protein expression (45%) were similar in mice in which the null allele occurred in a pure C57BL/6J genetic background versus a mixed (C57BL/6J X 129) background. Action potential duration did not differ between mice of different genotypes. Conclusions: A ~50% reduction of Cx43 expression causes significant conduction velocity slowing in the Cx43+/– mouse heart. The apparent lack of conduction velocity changes reported in previous studies may be related to technical factors rather than variations in genetic background. High-resolution optical mapping is a powerful tool for investigating molecular determinants of propagation and arrhythmias in genetically engineered mice.

KEYWORDS Cell communication; Gap junctions; Gene expression; Mapping


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?


This article has been cited by other articles:


Home page
Am. J. Physiol. Heart Circ. Physiol.Home page
R. W. Mills, S. M. Narayan, and A. D. McCulloch
Mechanisms of conduction slowing during myocardial stretch by ventricular volume loading in the rabbit
Am J Physiol Heart Circ Physiol, September 1, 2008; 295(3): H1270 - H1278.
[Abstract] [Full Text] [PDF]



Disclaimer:
Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.