J 2017

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

PÁSEK, Michal, Jiří ŠIMURDA a G. CHRISTÉ

Základní údaje

Originální název

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

Autoři

PÁSEK, Michal (203 Česká republika, garant, domácí), Jiří ŠIMURDA (203 Česká republika, domácí) a G. CHRISTÉ (250 Francie)

Vydání

Biomed Research International, New York, Hindawi Publishing Corporation, 2017, 2314-6133

Další údaje

Jazyk

angličtina

Typ výsledku

Článek v odborném periodiku

Obor

30400 3.4 Medical biotechnology

Stát vydavatele

Velká Británie a Severní Irsko

Utajení

není předmětem státního či obchodního tajemství

Impakt faktor

Impact factor: 2.583

Kód RIV

RIV/00216224:14110/17:00095655

Organizační jednotka

Lékařská fakulta

UT WoS

000396222700001

Klíčová slova anglicky

SODIUM-CALCIUM EXCHANGE; NA+-CA2+ EXCHANGE; CARDIAC MYOCYTES; FAILING HEARTS; NA/CA EXCHANGE; PROTEIN; CELLS; LOCALIZATION; MECHANISM; RELEASE

Štítky

Příznaky

Mezinárodní význam, Recenzováno
Změněno: 20. 3. 2018 18:31, Soňa Böhmová

Anotace

V originále

The ratio of densities of Na-Ca exchanger current (I-NaCa) in the t-tubular and surface membranes (I-NaCa-ratio) computed from the values of I-NaCa and membrane capacitances (C-m) 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 I-NaCa-ratio were simulated employing previously developed model of rat ventricular cell incorporating separate description of ion transport systems in the t-tubular and surface membranes. The increase of I-NaCa-ratio from 1.7 to 25 caused a prolongation of APD (duration of action potential at 90% repolarisation) by 12, 9, and 6% and an increase of peak intracellular Ca2+ transient by 45, 19, and 6% at 0.1, 1, and 5Hz, respectively. The prolonged APD resulted from the increase of I-NaCa due to the exposure of a larger fraction of Na-Ca exchangers to higher Ca2+ transients under the t-tubular membrane. The accompanying rise of Ca2+ transient was a consequence of a higher Ca2+ load in sarcoplasmic reticulum induced by the increased Ca2+ cycling between the surface and t-tubular membranes. However, the reason for large differences in the I-NaCa-ratio assessed from measurements in adult rat cardiomyocytes remains to be explained.

Návaznosti

NV16-30571A, projekt VaV
Název: Klinický význam a elektrofyziologické zhodnocení mutace c.926C>T genu KCNQ1 (p.T309I) jako možné „founder mutation“ syndromu dlouhého intervalu QT