Dog Ventricular Cell Model

This applet is used to simulate the activation of dog ventricular epicardial myocytes using the model by Fox, McHarg and Gilmour (Am J. Physiol. 2002; 282: H516-H530).

Using the applet, the myocyte can be paced at various cycle lengths and the final APD and DI are calculated automatically. In addition, it is possible to visualize the currents, gate variables, and ionic concentrations.

N(S1's) indicates how many S1 stimuli to apply.

S1 (bcl) indicates the cycle length for the S1 stimuli.

S2 (bcl) indicates the cycle length for the S2 stimulus.

Click "Start" to start the simulation. Use "Replot" to replot on the screen once a check box has been selected or a new value has been entered for S1, S2 or N. Use "Plot Currents" to plot the various currents of the model.

Things to try:

This model has short time memory effects that depend on gkr. Change N to 15 and the bcl of S1 and S2 to 190 and click replot. You'll see alternans in the APD. Now change gkr in the "option" button from 0.0136 to 0.0272 and observe no alternans develops.

To calculate points on APD restitution curves, change N, S1, and S2.

Click in the Ascii check box to obtain the voltage signal as a function of time. (Note that the larger the signal, the longer it takes for the window to appear.)