Detail publikace

A model of the guinea-pig ventricular cardiac myocyte incorporating a transverse-axial tubular system

PÁSEK, M. ŠIMURDA, J. ORCHARD, C. CHRISTÉ, G.

Originální název

A model of the guinea-pig ventricular cardiac myocyte incorporating a transverse-axial tubular system

Typ

článek v časopise - ostatní, Jost

Jazyk

angličtina

Originální abstrakt

A model of the guinea-pig cardiac ventricular myocyte has been developed that includes a representation of the transverse-axial tubular system (TATS), including heterogeneous distribution of ion flux pathways between the surface and tubular membranes. The model reproduces frequency-dependent changes of action potential shape and intracellular ion concentrations and can replicate experimental data showing ion diffusion between the tubular lumen and external solution in guinea-pig myocytes. The model is stable at rest and during activity and returns to rested state after perturbation. Theoretical analysis and model simulations show that, due to tight electrical coupling, tubular and surface membranes behave as a homogeneous whole during voltage and current clamp (maximum difference 0.9 mV at peak tubular INa of -38 nA). However during action potentials, restricted diffusion and ionic currents in TATS cause depletion of tubular Ca2+ and accumulation of tubular K+ (up to -19.8 % and +3.4 % respectively of bulk extracellular values, at 6 Hz). These changes, in turn, decrease ion fluxes across the TATS membrane and decrease SR Ca2+ load. Thus, the TATS plays a potentially important role in modulating the function of guinea-pig ventricular myocyte in physiological conditions.

Klíčová slova

ion accumulation, ion depletion; extracellular space; TATS; restricted diffusion; quantitative model

Autoři

PÁSEK, M.; ŠIMURDA, J.; ORCHARD, C.; CHRISTÉ, G.

Rok RIV

2008

Vydáno

30. 11. 2007

Nakladatel

ISSN 0079-6107

Místo

Great Britain

ISSN

0079-6107

Periodikum

PROGRESS IN BIOPHYSICS & MOLECULAR BIOLOGY

Ročník

2007 (96)

Číslo

1-3

Stát

Spojené království Velké Británie a Severního Irska

Strany od

258

Strany do

280

Strany počet

23

BibTex

@article{BUT45341,
  author="Michal {Pásek} and Jiří {Šimurda}",
  title="A model of the guinea-pig ventricular cardiac myocyte incorporating a transverse-axial tubular system",
  journal="PROGRESS IN BIOPHYSICS & MOLECULAR BIOLOGY",
  year="2007",
  volume="2007 (96)",
  number="1-3",
  pages="258--280",
  issn="0079-6107"
}