A MATHEMATICAL MODEL OF RAT VENTRICULAR CARDIOMYOCYTE WITH A NOVEL DESCRIPTION OF INTRACELLULAR AND T-TUBULAR Ca DYNAMICS
نویسندگان
چکیده
In this paper, we present a novel quantitative description of intracellular and t-tubular Ca dynamics in a model of rat cardiac ventricular myocyte. In order to simulate recently published data, the model incorporates t-tubular and peripheral dyads and intracellular subspaces, segmentation of the t-tubular luminal volume, reformulation of the inactivation properties of t-tubular and peripheral L-type calcium current (ICa) and a description of exogenous Ca buffer function in the intracellular space. The model is used to explore activity-induced changes of ion concentrations in the intracellular and t-tubular spaces and their role in excitation – contraction coupling in ventricular myocytes.
منابع مشابه
Different Densities of Na-Ca Exchange Current in T-Tubular and Surface Membranes and Their Impact on Cellular Activity in a Model of Rat Ventricular Cardiomyocyte
The ratio of densities of Na-Ca exchanger current (INaCa) in the t-tubular and surface membranes (INaCa-ratio) computed from the values of INaCa and membrane capacitances (Cm) measured in adult rat ventricular cardiomyocytes before and after detubulation ranges between 1.7 and 25 (potentially even 40). Variations of action potential waveform and of calcium turnover within this span of the INaCa...
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