(Circulation. 1996;94:3083-3086.)
© 1996 American Heart Association, Inc.
Articles |
the Cardiology Division, Department of Medicine, University of Pennsylvania School of Medicine and Cardiology Section, Medical Service, Philadelphia Veterans Affairs Medical Center, Philadelphia.
Correspondence to Sidney A. Cohen, MD, PhD, Cardiology Section (111C), Philadelphia VA Medical Center, University and Woodland Ave, Philadelphia, PA 19104. E-mail cohensa@mail.med.upenn.edu.
Background Of the five sodium channel subtypes expressed in cardiac tissues, the rat (rH1) and human (hH1) isoforms are thought to be the predominant subtypes on the basis of heterologous expression studies. In this study, subtype-specific antibodies and immunocytochemistry were used to confirm protein expression and to localize rH1 protein in cardiac tissues.
Methods and Results Subtype-specific antibodies immunolabeled adult rat heart tissue in a manner identical to that obtained with subtype-nonselective antibodies. All antibodies specifically bound to the surface and t-tubular systems of atrial and ventricular muscle cells. Cytoplasmic labeling, reflecting nascent sodium channels or cytoplasmic stores of sodium channel protein, was apparent. Most notably, all antibodies also specifically labeled the subset of intercalated disks located at the ends but not the sides of adjacent ventricular muscle cells.
Conclusions rH1 is the predominant subtype expressed on rat atrial and ventricular muscle cells. rH1 protein localization in surface and t-tubular membranes is consistent with its proposed role in coordinating membrane depolarization along the length and deep within cardiac muscle cells. rH1 protein localization in terminal intercalated disks suggests that sodium channels may also act as a localized voltage-dependent current amplifier, raising the safety margin for conduction; they also may contribute to anisotropic or saltatory conduction in cardiac tissues. These electrophysiological properties would be particularly important under conditions of altered channel function resulting from ion channel gene defects (eg, long QT syndrome), antiarrhythmic drug therapy, ischemia, or other heart diseases by influencing the electrophysiological substrate for ventricular tachyarrhythmias. (Circulation. 1996;94:3083-3086.)
Key Words: sodium channels ion channels immunohistochemistry intercalated disk conduction
This article has been cited by other articles:
![]() |
A. Maguy, S. Le Bouter, P. Comtois, D. Chartier, L. Villeneuve, R. Wakili, K. Nishida, and S. Nattel Ion Channel Subunit Expression Changes in Cardiac Purkinje Fibers: A Potential Role in Conduction Abnormalities Associated With Congestive Heart Failure Circ. Res., May 8, 2009; 104(9): 1113 - 1122. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. N. Dominguez, A. de la Rosa, F. Navarro, D. Franco, and A. E. Aranega Tissue distribution and subcellular localization of the cardiac sodium channel during mouse heart development Cardiovasc Res, April 1, 2008; 78(1): 45 - 52. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. Bennett and J. Healy Being there: cellular targeting of voltage-gated sodium channels in the heart J. Cell Biol., January 10, 2008; 180(1): 13 - 15. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. S. Lowe, O. Palygin, N. Bhasin, T. J. Hund, P. A. Boyden, E. Shibata, M. E. Anderson, and P. J. Mohler Voltage-gated Nav channel targeting in the heart requires an ankyrin-G dependent cellular pathway J. Cell Biol., January 10, 2008; 180(1): 173 - 186. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Abriel Roles and regulation of the cardiac sodium channel Nav1.5: Recent insights from experimental studies Cardiovasc Res, December 1, 2007; 76(3): 381 - 389. [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] |
||||
![]() |
B. Gavillet, J.-S. Rougier, A. A. Domenighetti, R. Behar, C. Boixel, P. Ruchat, H.-A. Lehr, T. Pedrazzini, and H. Abriel Cardiac Sodium Channel Nav1.5 Is Regulated by a Multiprotein Complex Composed of Syntrophins and Dystrophin Circ. Res., August 18, 2006; 99(4): 407 - 414. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. Brette and C. H. Orchard No Apparent Requirement for Neuronal Sodium Channels in Excitation-Contraction Coupling in Rat Ventricular Myocytes Circ. Res., March 17, 2006; 98(5): 667 - 674. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. F. Wiegerinck, A. O. Verkerk, C. N. Belterman, T. A.B. van Veen, A. Baartscheer, T. Opthof, R. Wilders, J. M.T. de Bakker, and R. Coronel Larger Cell Size in Rabbits With Heart Failure Increases Myocardial Conduction Velocity and QRS Duration Circulation, February 14, 2006; 113(6): 806 - 813. [Abstract] [Full Text] [PDF] |
||||
![]() |
L.S. Meadows and L.L. Isom Sodium channels as macromolecular complexes: Implications for inherited arrhythmia syndromes Cardiovasc Res, August 15, 2005; 67(3): 448 - 458. [Abstract] [Full Text] [PDF] |
||||
![]() |
V. Haufe, J. A. Camacho, R. Dumaine, B. Gunther, C. Bollensdorff, G. S. von Banchet, K. Benndorf, and T. Zimmer Expression pattern of neuronal and skeletal muscle voltage-gated Na+ channels in the developing mouse heart J. Physiol., May 1, 2005; 564(3): 683 - 696. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. J. Mohler, I. Rivolta, C. Napolitano, G. LeMaillet, S. Lambert, S. G. Priori, and V. Bennett Nav1.5 E1053K mutation causing Brugada syndrome blocks binding to ankyrin-G and expression of Nav1.5 on the surface of cardiomyocytes PNAS, December 14, 2004; 101(50): 17533 - 17538. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. D. Malhotra, V. Thyagarajan, C. Chen, and L. L. Isom Tyrosine-phosphorylated and Nonphosphorylated Sodium Channel {beta}1 Subunits Are Differentially Localized in Cardiac Myocytes J. Biol. Chem., September 24, 2004; 279(39): 40748 - 40754. [Abstract] [Full Text] [PDF] |
||||
![]() |
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] |
||||
![]() |
H. B. Rasmussen, M. Moller, H.-G. Knaus, B. S. Jensen, S.-P. Olesen, and N. K. Jorgensen Subcellular localization of the delayed rectifier K+ channels KCNQ1 and ERG1 in the rat heart Am J Physiol Heart Circ Physiol, April 1, 2004; 286(4): H1300 - H1309. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. K.G. Maier, R. E. Westenbroek, K. A. McCormick, R. Curtis, T. Scheuer, and W. A. Catterall Distinct Subcellular Localization of Different Sodium Channel {alpha} and {beta} Subunits in Single Ventricular Myocytes From Mouse Heart Circulation, March 23, 2004; 109(11): 1421 - 1427. [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] |
||||
![]() |
B. J.J.M Brundel, J. Ausma, I. C van Gelder, J. J.L Van Der Want, W. H van Gilst, H. J.G.M Crijns, and R. H Henning Activation of proteolysis by calpains and structural changes in human paroxysmal and persistent atrial fibrillation Cardiovasc Res, May 1, 2002; 54(2): 380 - 389. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. K. G. Maier, R. E. Westenbroek, K. A. Schenkman, E. O. Feigl, T. Scheuer, and W. A. Catterall An unexpected role for brain-type sodium channels in coupling of cell surface depolarization to contraction in the heart PNAS, March 19, 2002; 99(6): 4073 - 4078. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. S. Spach Mechanisms of the Dynamics of Reentry in a Fibrillating Myocardium : Developing a Genes-to-Rotors Paradigm Circ. Res., April 27, 2001; 88(8): 753 - 755. [Full Text] [PDF] |
||||
![]() |
J. D. Malhotra, C. Chen, I. Rivolta, H. Abriel, R. Malhotra, L. N. Mattei, F. C. Brosius, R. S. Kass, and L. L. Isom Characterization of Sodium Channel {{alpha}}- and {beta}-Subunits in Rat and Mouse Cardiac Myocytes Circulation, March 6, 2001; 103(9): 1303 - 1310. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. R Bezzina, M. B Rook, and A. A.M Wilde Cardiac sodium channel and inherited arrhythmia syndromes Cardiovasc Res, February 1, 2001; 49(2): 257 - 271. [Full Text] [PDF] |
||||
![]() |
H. Dobrzynski, S. M. Rothery, D. D.R. Marples, S. R. Coppen, Y. Takagishi, H. Honjo, M. M. Tamkun, Z. Henderson, I. Kodama, N. J. Severs, et al. Presence of the Kv1.5 K+ Channel in the Sinoatrial Node J. Histochem. Cytochem., June 1, 2000; 48(6): 769 - 780. [Abstract] [Full Text] |
||||
![]() |
M. S. Spach, J. F. Heidlage, P. C. Dolber, and R. C. Barr Electrophysiological Effects of Remodeling Cardiac Gap Junctions and Cell Size : Experimental and Model Studies of Normal Cardiac Growth Circ. Res., February 18, 2000; 86(3): 302 - 311. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. M. Roden and S. Kupershmidt From genes to channels: normal mechanisms Cardiovasc Res, May 1, 1999; 42(2): 318 - 326. [Abstract] [Full Text] [PDF] |
||||
![]() |
K. Petrecca, R. Atanasiu, S. Grinstein, J. Orlowski, and A. Shrier Subcellular localization of the Na+/H+ exchanger NHE1 in rat myocardium Am J Physiol Heart Circ Physiol, February 1, 1999; 276(2): H709 - H717. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. E. Saffitz and K. A. Yamada Do Alterations in Intercellular Coupling Play a Role in Cardiac Contractile Dysfunction? Circulation, February 24, 1998; 97(7): 630 - 632. [Full Text] [PDF] |
||||
![]() |
R. R. Kaprielian, M. Gunning, E. Dupont, M. N. Sheppard, S. M. Rothery, R. Underwood, D. J. Pennell, K. Fox, J. Pepper, P. A. Poole-Wilson, et al. Downregulation of Immunodetectable Connexin43 and Decreased Gap Junction Size in the Pathogenesis of Chronic Hibernation in the Human Left Ventricle Circulation, February 24, 1998; 97(7): 651 - 660. [Abstract] [Full Text] [PDF] |
||||
|
Circulation Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 1996 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |