Interbeat interval modulation in the sinoatrial node as a result of membrane current stochasticity-a theoretical and numerical study.

ABSTRACT: A single isolated sinoatrial pacemaker cell presents intrinsic interbeat interval (IBI) variability that is believed to result from the stochastic characteristics of the opening and closing processes of membrane ion channels. To our knowledge, a novel mathematical framework was developed in this work to address the effect of current fluctuations on the IBIs of sinoatrial pacemaker cells. Using statistical modeling and employing the Fokker-Planck formalism, our mathematical analysis suggests that increased stochastic current fluctuation variance linearly increases the slope of phase-4 depolarization, hence the rate of activations. Single-cell and two-dimensional computerized numerical modeling of the sinoatrial node was conducted to validate the theoretical predictions using established ion

SUBMITTER: Dvir H 

PROVIDER: S-EPMC4375434 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature