Fox-McHarg-Gilmour Model
for one canine ventricular cell
This model is used to simulate the activation of canine ventricular cells using the
model of Fox et al.
To use the applet, click the Start button to initiate
the simulation and the Reset button to return
the parameters to their initial values. Check the box for each
variable to plot it in the window.
The final action potential duration (APD)
and diastolic interval (DI) are calculated automatically.
Press the Plot Currents button to view the individual transmembrane currents.
N(s1's) indicates the number of stimuli given at the
cycle length indicated by S1 (bcl).
S2 indicates the timing of the last stimulus.
Things to try:
Uncheck the Voltage box and check the boxes for some of the other variables.
Change N(S1's), S1, and S2 to calculate points on APD restitution curves.
After pressing the Plot Currents button, check the Ascii data 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.)
Observe this model's short-term 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
action potential duration. Now change gkr from 0.0136 to 0.0272 and
observe that no alternans develop.
Fox JJ, McHarg J, Gilmour RF, Jr. (2002)
Am J Physiol Heart Circ Physiol 282, H516-H530.