(Circulation. 2001;104:2095.)
© 2001 American Heart Association, Inc.
Basic Science Reports |
From the Department of Medicine, Montreal Heart Institute and University of Montreal (W.H., D.C., D.L., S.N.) and the Department of Pharmacology, McGill University (W.H., S.N.), Montreal, Quebec, Canada.
Correspondence to Stanley Nattel, Montreal Heart Institute Research Center, 5000 Belanger St East, Montreal, Quebec, H1T 1C8, Canada. E-mail nattel{at}icm.umontreal.ca
Background Cardiac Purkinje cells (PCs) are important for the generation of triggered arrhythmias, particularly in association with abnormal repolarization. The effects of congestive heart failure (CHF) on the ionic properties of PCs are unknown.
Methods and Results PCs were isolated from false tendons of control dogs and dogs with ventricular tachypacing-induced CHF. CHF PCs were hypertrophied (capacitance, mean±SEM, 149±4 pF, n=130; versus 128±3 pF, n=150, control; P<0.001). Transient outward current density was reduced in CHF PCs without change in voltage dependence or kinetics. CHF also reduced inward-rectifier current density, with no change in form of the current-voltage relationship. Densities of L- and T-type calcium, rapid and slow delayed rectifier, and Na+-Ca2+ exchange currents were unaltered by CHF, but L-type calcium current inactivation was slowed at positive potentials. Purkinje fiber action potentials from CHF dogs showed decreased phase 1 amplitudes and elevated plateau voltages and demonstrated twice as much prolongation on exposure to the rapid delayed rectifier blocker E-4031 as control Purkinje fibers.
Conclusions CHF causes remodeling of important K+ and Ca2+ currents in cardiac PCs, decreasing repolarization reserve and causing an exaggerated repolarization delay in response to a class III drug. These results have important potential implications regarding ventricular arrhythmogenesis, particularly related to triggered activity in PCs, in patients with CHF.
Key Words: ion channels remodeling electrophysiology antiarrhythmia agents heart failure
This article has been cited by other articles:
![]() |
D. Guo, L. Young, C. Patel, Z. Jiao, Y. Wu, T. Liu, P. R. Kowey, and G.-X. Yan Calcium-activated chloride current contributes to action potential alternations in left ventricular hypertrophy rabbit Am J Physiol Heart Circ Physiol, July 1, 2008; 295(1): H97 - H104. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. G. Akar The Perfect Storm: Defective Calcium Cycling in Insulated Fibers With Reduced Repolarization Reserve Circ. Res., November 9, 2007; 101(10): 968 - 970. [Full Text] [PDF] |
||||
![]() |
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] |
||||
![]() |
Y. Tsuji, S. Zicha, X.-Y. Qi, I. Kodama, and S. Nattel Potassium Channel Subunit Remodeling in Rabbits Exposed to Long-Term Bradycardia or Tachycardia: Discrete Arrhythmogenic Consequences Related to Differential Delayed-Rectifier Changes Circulation, January 24, 2006; 113(3): 345 - 355. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Collins, H. Wang, and M. K. Larson Differential Sensitivity of Kir2 Inward-Rectifier Potassium Channels to a Mitochondrial Uncoupler: Identification of a Regulatory Site Mol. Pharmacol., April 1, 2005; 67(4): 1214 - 1220. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. F. Tomaselli and D. P. Zipes What Causes Sudden Death in Heart Failure? Circ. Res., October 15, 2004; 95(8): 754 - 763. [Abstract] [Full Text] [PDF] |
||||
![]() |
N. Ueda, D. P Zipes, and J. Wu Prior ischemia enhances arrhythmogenicity in isolated canine ventricular wedge model of long QT 3 Cardiovasc Res, July 1, 2004; 63(1): 69 - 76. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. Zicha, I. Moss, B. Allen, A. Varro, J. Papp, R. Dumaine, C. Antzelevich, and S. Nattel Molecular basis of species-specific expression of repolarizing K+ currents in the heart Am J Physiol Heart Circ Physiol, October 1, 2003; 285(4): H1641 - H1649. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. O. Verkerk, R. Wilders, R. Coronel, J. H. Ravesloot, and E. E. Verheijck Ionic Remodeling of Sinoatrial Node Cells by Heart Failure Circulation, August 12, 2003; 108(6): 760 - 766. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Pourrier, S. Zicha, J. Ehrlich, W. Han, and S. Nattel Canine Ventricular KCNE2 Expression Resides Predominantly in Purkinje Fibers Circ. Res., August 8, 2003; 93(3): 189 - 191. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. Han, L. Zhang, G. Schram, and S. Nattel Properties of potassium currents in Purkinje cells of failing human hearts Am J Physiol Heart Circ Physiol, December 1, 2002; 283(6): H2495 - H2503. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. Han, W. Bao, Z. Wang, and S. Nattel Comparison of Ion-Channel Subunit Expression in Canine Cardiac Purkinje Fibers and Ventricular Muscle Circ. Res., November 1, 2002; 91(9): 790 - 797. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Schram, M. Pourrier, P. Melnyk, and S. Nattel Differential Distribution of Cardiac Ion Channel Expression as a Basis for Regional Specialization in Electrical Function Circ. Res., May 17, 2002; 90(9): 939 - 950. [Abstract] [Full Text] [PDF] |
||||
|
Circulation Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 2001 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |