| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
(Circulation. 2003;108:760.)
© 2003 American Heart Association, Inc.
Basic Science Reports |
From the Department of Physiology (A.O.V., R.W., J.H.R., E.E.V.) and Experimental and Molecular Cardiology Group (A.O.V., R.C.), Academic Medical Center, University of Amsterdam, The Netherlands; and the Department of Cardiology (R.C.), Heart Lung Center Utrecht, Utrecht, The Netherlands.
Correspondence to Arie Verkerk, AMC, Department of Physiology, Meibergdreef 15, 1105 AZ Amsterdam, The Netherlands. E-mail A.O.Verkerk{at}amc.uva.nl
Received March 6, 2003; revision received April 18, 2003; accepted April 21, 2003.
Background In animal models of heart failure (HF), heart rate decreases as the result of an increase in intrinsic cycle length of the sinoatrial node (SAN). In this study, we evaluate the HF-induced remodeling of membrane potentials and currents in SAN cells.
Methods and Results SAN cells were isolated from control rabbits and rabbits with volume and pressure overloadinduced HF and patch-clamped to measure their electrophysiological properties. HF cells were not hypertrophied (capacitance, mean±SEM, 52±3 versus 50±4 pF in control). HF increased intrinsic cycle length by 15% and decreased diastolic depolarization rate by 30%, whereas other action potential parameters were unaltered. In HF, the hyperpolarization-activated "pacemaker" current (If) and slow component of the delayed rectifier current (IKs) were reduced by 40% and 20%, respectively, without changes in voltage dependence or kinetics. T-type and L-type calcium current, rapid and ultrarapid delayed rectifier current, transient outward currents, and sodium-calcium exchange current were unaltered.
Conclusions In single SAN cells of rabbits with HF, intrinsic cycle length is increased as the result of a decreased diastolic depolarization rate rather than a change in action potential duration. HF reduced both If and IKs density. Since IKs plays a limited role in pacemaker activity, the HF-induced decrease in heart rate is attributable to remodeling of If.
Key Words: sinoatrial node remodeling ion channels action potentials
This article has been cited by other articles:
![]() |
D. Duan Phenomics of cardiac chloride channels: the systematic study of chloride channel function in the heart J. Physiol., May 1, 2009; 587(10): 2163 - 2177. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y.-H. Yeh, B. Burstein, X. Y. Qi, M. Sakabe, D. Chartier, P. Comtois, Z. Wang, C.-T. Kuo, and S. Nattel Funny Current Downregulation and Sinus Node Dysfunction Associated With Atrial Tachyarrhythmia: A Molecular Basis for Tachycardia-Bradycardia Syndrome Circulation, March 31, 2009; 119(12): 1576 - 1585. [Abstract] [Full Text] [PDF] |
||||
![]() |
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] |
||||
![]() |
A. O. Verkerk, R. Wilders, M. M.G.J. van Borren, R. J.G. Peters, E. Broekhuis, K. Lam, R. Coronel, J. M.T. de Bakker, and H. L. Tan Pacemaker current (If) in the human sinoatrial node Eur. Heart J., October 2, 2007; 28(20): 2472 - 2478. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Cheng, K. Kinard, R. Rajamani, and M. C. Sanguinetti Molecular Mapping of the Binding Site for a Blocker of Hyperpolarization-Activated, Cyclic Nucleotide-Modulated Pacemaker Channels J. Pharmacol. Exp. Ther., September 1, 2007; 322(3): 931 - 939. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. O. Verkerk, A. C.G. van Ginneken, T. A.B. van Veen, and H. L. Tan Effects of heart failure on brain-type Na+ channels in rabbit ventricular myocytes Europace, August 1, 2007; 9(8): 571 - 577. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Dobrzynski, M. R. Boyett, and R. H. Anderson New Insights Into Pacemaker Activity: Promoting Understanding of Sick Sinus Syndrome Circulation, April 10, 2007; 115(14): 1921 - 1932. [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] |
||||
![]() |
T. Krogh-Madsen, P. Schaffer, A. D. Skriver, L. K. Taylor, B. Pelzmann, B. Koidl, and M. R. Guevara An ionic model for rhythmic activity in small clusters of embryonic chick ventricular cells Am J Physiol Heart Circ Physiol, July 1, 2005; 289(1): H398 - H413. [Abstract] [Full Text] [PDF] |
||||
![]() |
W. R. Giles Supraventricular pacemaker activity in the canine heart: Contributions from HCN channels in control conditions and in a model of heart failure Cardiovasc Res, June 1, 2005; 66(3): 430 - 432. [Full Text] [PDF] |
||||
![]() |
S. Zicha, M. Fernandez-Velasco, G. Lonardo, N. L'Heureux, and S. Nattel Sinus node dysfunction and hyperpolarization-activated (HCN) channel subunit remodeling in a canine heart failure model Cardiovasc Res, June 1, 2005; 66(3): 472 - 481. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. J Janse Electrophysiological changes in heart failure and their relationship to arrhythmogenesis Cardiovasc Res, February 1, 2004; 61(2): 208 - 217. [Abstract] [Full Text] [PDF] |
||||
|
Circulation Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 2003 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |