J Physiol Society Membership
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

J Physiol Vol 501, Issue Pt 2 pp 263-274
Copyright © 1997 by The Physiological Society
This Article
Right arrow Full Text (PDF)
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 Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Petrecca, K
Right arrow Articles by Shrier, A
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Petrecca, K
Right arrow Articles by Shrier, A

Sodium channel distribution within the rabbit atrioventricular node as analysed by confocal microscopy.

 K Petrecca, F Amellal, D W Laird, S A Cohen and A Shrier

Department of Physiology, McGill University, Montreal, Quebec, Canada.

1. Paired 20 microns thick sections of fresh frozen tissue taken from the frontal plane of the rabbit atrioventricular (AV) nodal region were processed for histology and immunohistochemistry. Confocal microscopy was used to image the distribution of sodium channels using IgG (R12) developed against a highly conserved sequence in the interdomain 3-4 region of cloned sodium channels. 2. In ventricular and atrial cells, sodium channel immunofluorescence was localized to lateral membranes and T-tubules. In the open AV node, levels of sodium channel immunofluorescence in the transitional cell zone and in the lower nodal cell tract were comparable to that found in the atrial and ventricular myocardium. 3. In the enclosed AV node a gradation of sodium channel immunofluorescence is present such that peripherally located circumferential transitional cells display high levels of immunofluorescence, comparable to that of atrial and ventricular myocardium, while centrally located midnodal cells display decreased levels of or no immunofluorescence. 4. In order to correlate the distribution of sodium channels with the distribution of gap junctions, we used IgG directed against the carboxyl terminus of connexin43 (CT-360). Ventricular cell immunofluorescence was localized primarily to the intercalated disk region, while in the AV node, the pattern of distribution was found to be similar to that of sodium channels. 5. The reduced levels of and/or absence of immunofluorescence in the midnodal cell region indicates a paucity of sodium channel and connexin43 protein expression in this region of the AV node that would favour slow impulse conduction.




This article has been cited by other articles:


Home page
 Physiol. Rev.Home page
M. E. Mangoni and J. Nargeot
Genesis and Regulation of the Heart Automaticity
Physiol Rev, July 1, 2008; 88(3): 919 - 982.
[Abstract] [Full Text] [PDF]

Home page
 Physiol. Rev.Home page
J. M. Nerbonne and R. S. Kass
Molecular Physiology of Cardiac Repolarization
Physiol Rev, October 1, 2005; 85(4): 1205 - 1253.
[Abstract] [Full Text] [PDF]

Home page
 Cardiovasc ResHome page
A. J Workman, K. A Kane, and A. C Rankin
Ionic basis of a differential effect of adenosine on refractoriness in rabbit AV nodal and atrial isolated myocytes
Cardiovasc Res, September 1, 1999; 43(4): 974 - 984.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Copyright © 1997 The Physiological Society.