Slow inactivation of the sodium current in rabbit cardiac Purkinje fibres

1987 ◽  
Vol 408 (1) ◽  
pp. 18-26 ◽  
Author(s):  
E. Carmeliet
Keyword(s):  
Sodium Current ◽  
Slow Inactivation ◽  
Purkinje Fibres ◽  
Cardiac Purkinje Fibres

scholarly journals A Mathematical Model for the Cardiac Action Potential Based on Slow Inactivation of Sodium Conductance

1968 ◽  
Vol 21 (1) ◽  
pp. 37 ◽  
Author(s):  
L Munk ◽  
E PGeorge
Keyword(s):  
Mathematical Model ◽  
Action Potential ◽  
Action Potentials ◽  
Sodium Current ◽  
Potassium Conductance ◽  
Slow Inactivation ◽  
Squid Axon ◽  
Purkinje Fibres ◽  
Cardiac Action ◽  
Potassium Conductances

A mathematical model for the action potential in Purkinje fibres is developed. It is based on voltage-clamp results which show that inactivation of sodium current in these muscles is much slower than in squid axon and that the latent rise in potassium conductance is not present. Both the sodium and the potassium conductances are represented as a sum of slow and fast components. This is incorporated in the suitably adjusted Hodgkin-Huxley model for the squid axon. It is shown that such a model can account satisfactorily for the shape of the action potentials in Purkinje fibres.

Tl+-Ions: Effects on the Automaticity of Sinoatrial Tissue and on dV/dtmax and iK2 of Cardiac Purkinje Fibres

1982 ◽  
Vol 37 (10) ◽  
pp. 1006-1014 ◽  
Author(s):  
C. chenbach ◽  
J. Wiemer ◽  
R. Ziskoven ◽  
U. Winter
Keyword(s):  
Guinea Pig ◽  
Cardiac Tissue ◽  
Sodium Current ◽  
Sinus Node ◽  
Beat Frequency ◽  
Contractile Force ◽  
Inactivation Kinetics ◽  
Purkinje Fibres ◽  
Thallium Poisoning ◽  
Cardiac Purkinje Fibres

The disrhythmic effects of thallium were investigated in various cardiac tissues to determine the primary site of intoxication with respect to ensuing arrhythmias. In isolated cardiac tissue Lameijer and van Zwieten [1] had contended that arrhythmias arise from the sinus node after thallium poisoning. To test this hypothesis we administered concentrations of Tl+ between 10"7 and 10-4 ᴍ to guinea pig sino-atrial preparations, to guinea pig papillary muscles and to sheep cardiac Purkinje fibres. In sino-artial preparations thallium provoked increases and decreases of spontaneous beat frequency which were not linked to corresponding changes in contractile force. In conductive tissue, Purkinje fibres, the inactivation kinetics of the fast sodium current and the pacemaker current iK2 were investigated by voltage clamp experiments. Here, thallium was seen to be essentially without toxic effects which could account for arrhythmias. In ventricular muscle actions potentials and contractile force were recorded simultaneously. Here again, ventricular arrhythmias are not to be expected from thallium intoxication in rather high concentrations. The findings support the view that arrhythmogenic effects of thallium are restricted to the sinus node.

The steady state TTX-sensitive (?window?) sodium current in cardiac Purkinje fibres

1979 ◽  
Vol 379 (2) ◽  
pp. 137-142 ◽  
Author(s):  
David Attwell ◽  
Ira Cohen ◽  
David Eisner ◽  
Mitsuyoshi Ohba ◽  
Carlos Ojeda
Keyword(s):  
Steady State ◽  
Sodium Current ◽  
Purkinje Fibres ◽  
Cardiac Purkinje Fibres
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