Cardiac models of circadian rhythms in early afterdepolarizations & arrhythmias (Diekman & Wei 2021)

 Download zip file 
Help downloading and running models
We fit a simplified Luo-Rudy model to voltage-clamp data showing a circadian rhythm in L-type calcium conductance. Simulations of the model (single-cell and 2-D spatial versions) suggest that circadian rhythms in early afterdepolarizations may contribute to daily rhythms in cardiac arrhythmias and sudden cardiac death.
1 . Diekman CO, Wei N (2021) Circadian Rhythms of Early Afterdepolarizations and Ventricular Arrhythmias in a Cardiomyocyte Model. Biophys J 120:319-333 [PubMed]
Model Information (Click on a link to find other models with that property)
Model Type: Neuron or other electrically excitable cell;
Brain Region(s)/Organism:
Cell Type(s): Cardiac ventricular cell;
Channel(s): I Calcium; I K;
Gap Junctions:
Simulation Environment: MATLAB;
Model Concept(s): Circadian Rhythms; Action Potentials; Cardiac pacemaking; Bifurcation;
Implementer(s): Diekman, Casey O. [casey.o.diekman at];
Search NeuronDB for information about:  I K; I Calcium;
function z = diekman_wei_model(~,u)

% equations for modified Sato et al 2010 model 

global g_ca g_k Iapp Eca Ek tauf taux
global dhalf dslope fhalf fslope xhalf xslope

V = u(1);
f = u(2);
x = u(3);

dinf = 1/(1+exp(-(V+dhalf)/dslope));
finf = 1/(1+exp((V+fhalf)/fslope));
xinf = 1/(1+exp(-(V+xhalf)/xslope));

Ica = g_ca*dinf*f*(V-Eca);
Ik = g_k*x*(V-Ek);

z(1) = Iapp - Ica - Ik;
z(2) = (finf - f)/tauf;
z(3) = (xinf - x)/taux;


Loading data, please wait...