| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Articles in PresS, published online ahead of print November 29, 2001
Am J Physiol Heart Circ Physiol, 10.1152/ajpheart.00489.2001
Submitted on June 4, 2001
Accepted on November 20, 2001
1 Research Center, Montreal Heart Institute, Montreal, Quebec, Canada
* To whom correspondence should be addressed. E-mail: nattel{at}icm.umontreal.ca.
Ionically-based cardiac action potential (AP) models are based on equations with singular Jacobians and display time-dependent AP and ionic changes (transients), which may be due to this mathematical limitation. The present study evaluated transients during long-term simulated activity in a mathematical model of the canine atrial AP. Stimulus current assignment to a specific ionic species contributed to stability. Ionic concentrations were least disturbed with K+-stimulus current. All parameters stabilized within 6 to 7 h. Inward-rectifier, Na+/Ca2+-exchanger, L-type Ca2+, and Na+/Cl- co-transporter currents made the greatest contributions to stabilization of intracellular [K+], [Na+], [Ca2+] and [Cl-]respectively. Time-dependent AP-shortening was largely due to outward shift of Na+/Ca2+-exchange related to Na+i accumulation. AP duration (APD) reached steady state after ~40 min. AP transients also occurred in canine atrial preparations, with APD decreasing by ~10 ms over 35 min, compared to ~27 ms in the model. We conclude that model APD and ionic transients stabilize with appropriate stimulus current assignment and that the mathematical limitation of equation singularity does not preclude meaningful longterm simulations. The model agrees qualitatively with experimental observations, but quantitative discrepancies highlight limitations of long-term model simulations.
This article has been cited by other articles:
|
|
 |
|
  V. A. Maltsev and E. G. Lakatta Synergism of coupled subsarcolemmal Ca2+ clocks and sarcolemmal voltage clocks confers robust and flexible pacemaker function in a novel pacemaker cell model Am J Physiol Heart Circ Physiol, March 1, 2009; 296(3): H594 - H615. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
V. Jacquemet and C. S. Henriquez Loading effect of fibroblast-myocyte coupling on resting potential, impulse propagation, and repolarization: insights from a microstructure model Am J Physiol Heart Circ Physiol, May 1, 2008; 294(5): H2040 - H2052. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. Tsujimae, S. Suzuki, S. Murakami, and Y. Kurachi Frequency-dependent effects of various IKr blockers on cardiac action potential duration in a human atrial model Am J Physiol Heart Circ Physiol, July 1, 2007; 293(1): H660 - H669. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R. Otway, J. I. Vandenberg, G. Guo, A. Varghese, M. L. Castro, J. Liu, J. Zhao, J. A. Bursill, K. R. Wyse, H. Crotty, et al. Stretch-Sensitive KCNQ1 Mutation: A Link Between Genetic and Environmental Factors in the Pathogenesis of Atrial Fibrillation? J. Am. Coll. Cardiol., February 6, 2007; 49(5): 578 - 586. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Zou, J. Kneller, L. J. Leon, and S. Nattel Substrate size as a determinant of fibrillatory activity maintenance in a mathematical model of canine atrium Am J Physiol Heart Circ Physiol, September 1, 2005; 289(3): H1002 - H1012. [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]
|
|
|
|
 |
|
 T. J. Hund and Y. Rudy Rate Dependence and Regulation of Action Potential and Calcium Transient in a Canine Cardiac Ventricular Cell Model Circulation, November 16, 2004; 110(20): 3168 - 3174. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. R. Ehrlich, T.-J. Cha, L. Zhang, D. Chartier, L. Villeneuve, T. E. Hebert, and S. Nattel Characterization of a hyperpolarization-activated time-dependent potassium current in canine cardiomyocytes from pulmonary vein myocardial sleeves and left atrium J. Physiol., June 1, 2004; 557(2): 583 - 597. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
J. R Ehrlich, T.-J. Cha, L. Zhang, D. Chartier, P. Melnyk, S. H Hohnloser, and S. Nattel Cellular electrophysiology of canine pulmonary vein cardiomyocytes: action potential and ionic current properties J. Physiol., September 15, 2003; 551(3): 801 - 813. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Cabo and P. A. Boyden Electrical remodeling of the epicardial border zone in the canine infarcted heart: a computational analysis Am J Physiol Heart Circ Physiol, January 1, 2003; 284(1): H372 - H384. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Kneller, R. Zou, E. J. Vigmond, Z. Wang, L. J. Leon, and S. Nattel Cholinergic Atrial Fibrillation in a Computer Model of a Two-Dimensional Sheet of Canine Atrial Cells With Realistic Ionic Properties Circ. Res., May 17, 2002; 90 (9): e73 - e87. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |
