Title
Induced pacemaker activity in virtual mammalian ventricular cells
Abstract
The stability of induced pacemaker activity in a virtual human ventricular cell is analysed by numerical simulations and continuation algorithms, with the conductance of the time independent inward rectifying potassium current (IK1) as the bifurcation parameter. Autorhythmicity is induced within a narrow range of this conductance, where periodic oscillations and bursting behaviour are observed. The frequency of the oscillations approaches zero as the parameter moves towards the bifurcation point, suggesting a homoclinic bifurcation. Intracellular sodium ([Na+]i) and calcium ([Ca2+]i) concentration dynamics can influence the location of the bifurcation point and the stability of the periodic states. These two concentrations function as slow variables, pushing the fast membrane voltage system into and out of the periodic region, producing bursting behaviour. Moreover, suppressing IK1 will prolong action potential duration and may introduce risks of developing stable periodic intermittency and arrhythmia. A genetically engineered pacemaker may appear an attractive idea, but simple analysis suggests inherent problems.
Year
DOI
Venue
2005
10.1007/11494621_23
FIMH
Keywords
Field
DocType
periodic state,virtual mammalian ventricular cell,stable periodic intermittency,periodic oscillation,bifurcation point,induced pacemaker activity,parameter move,periodic region,oscillations approach,homoclinic bifurcation,bifurcation parameter,oscillations,numerical simulation,genetic engineering,virtual human
Bursting,Oscillation,Homoclinic bifurcation,Membrane potential,Pacemaker potential,Control theory,Biophysics,Bifurcation theory,Intermittency,Bifurcation,Physics
Conference
Volume
ISSN
ISBN
3504
0302-9743
3-540-26161-3
Citations 
PageRank 
References 
1
0.63
1
Authors
2
Name
Order
Citations
PageRank
Wing Chiu Tong110.63
Arun V. Holden25220.71