AJP - Heart Calcium Transients and Cell-Sarcomere
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

Am J Physiol Heart Circ Physiol 279: H2095-H2103, 2000;
0363-6135/00 $5.00
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Right arrow Citation Map
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in ISI Web of Science
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 ISI Web of Science (8)
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Wang, Y.-G.
Right arrow Articles by Joyner, R. W.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Wang, Y.-G.
Right arrow Articles by Joyner, R. W.
Vol. 279, Issue 5, H2095-H2103, November 2000

Fast pacing facilitates discontinuous action potential propagation between rabbit atrial cells

Yang-Gan Wang, Mary B. Wagner, Rajiv Kumar, William N. Goolsby, and Ronald W. Joyner

Todd Franklin Cardiac Research Laboratory, Children's Heart Center, Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia 30322

We examined the critical coupling conductance (GC) for propagation at different pacing cycle lengths (CLs) (1,000 and 400 ms). As GC was progressively reduced, propagation failed at a CL of 1,000 ms, whereas propagation succeeded at a CL of 400 ms over a range of GC values before failing at a CL of 400 ms at a lower GC, showing facilitation of propagation at the shorter CL. Critical GC was (means ± SE) 0.8 ± 0.1 nS for a CL of 400 ms and 1.3 ± 0.1 nS for a CL of 1,000 ms (a 63% increase, P < 0.002, n = 9 cell pairs). In 14 uncoupled cells, action potential duration at 30% repolarization (APD30) increased from 19.9 ± 2.5 to 41.8 ± 2.6 ms (P < 0.001) as CL decreased from 1,000 to 400 ms. In five cell pairs, critical GC with 4-aminopyridine (4-AP) was reduced to 0.4 ± 0.1 nS at a CL of 1,000 ms (P < 0.05 compared with control solution), and critical GC in 4-AP was unchanged by decreasing CL to 400 ms. It is possible that the "remodeling" of atrial cells due to atrial fibrillation or tachycardia, which has been shown to produce a decrease in the transient outward current, may result in an enhanced ability to propagate, possibly facilitating further development of fibrillation under conditions of decreased cellular coupling.

electrophysiology; heart; arrhythmias


This article has been cited by other articles:


Home page
 Physiol. Rev.Home page
S. Nattel, A. Maguy, S. Le Bouter, and Y.-H. Yeh
Arrhythmogenic Ion-Channel Remodeling in the Heart: Heart Failure, Myocardial Infarction, and Atrial Fibrillation
Physiol Rev, April 1, 2007; 87(2): 425 - 456.
[Abstract] [Full Text] [PDF]

Home page
 Physiol. Rev.Home page
A. G. KLEBER and Y. RUDY
Basic Mechanisms of Cardiac Impulse Propagation and Associated Arrhythmias
Physiol Rev, April 1, 2004; 84(2): 431 - 488.
[Abstract] [Full Text] [PDF]

Home page
 Cardiovasc ResHome page
D. J. Huelsing, A. E. Pollard, and K. W. Spitzer
Transient outward current modulates discontinuous conduction in rabbit ventricular cell pairs
Cardiovasc Res, March 1, 2001; 49(4): 779 - 789.
[Abstract] [Full Text] [PDF]


HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
Visit Other APS Journals Online