Local Control Model of a Human Ventricular Myocyte: An Exploration of Frequency-Dependent Changes and Calcium Sparks.

ABSTRACT: Calcium (Ca²⁺) sparks are the elementary events of excitation-contraction coupling, yet they are not explicitly represented in human ventricular myocyte models. A stochastic ventricular cardiomyocyte human model that adapts to intracellular Ca²⁺ ([Ca²⁺]_i) dynamics, spark regulation, and frequency-dependent changes in the form of locally controlled Ca²⁺ release was developed. The 20,000 CRUs in this model are composed of 9 individual LCCs and 49 RyRs that function as couplons. The simulated action potential duration at 1 Hz steady-state pacing is ~0.280 s similar to human ventricular cell recordings. Rate-dependence experiments reveal that APD shortening mechanisms are largely contributed by the L-type calcium channel inactivation, RyR

SUBMITTER: Alvarez JAE 

PROVIDER: S-EPMC10452762 | biostudies-literature | 2023 Aug

REPOSITORIES: biostudies-literature