Fraction of the T-Tubular Membrane as an Important Parameter in
Cardiac Cellular Electrophysiology: A New Way of Estimation

J 2022

Fraction of the T-Tubular Membrane as an Important Parameter in Cardiac Cellular Electrophysiology: A New Way of Estimation

ŠVECOVÁ, Olga, Markéta BÉBAROVÁ, Milena ŠIMURDOVÁ and Jiří ŠIMURDA

Basic information

Original name

Fraction of the T-Tubular Membrane as an Important Parameter in Cardiac Cellular Electrophysiology: A New Way of Estimation

Authors

ŠVECOVÁ, Olga (203 Czech Republic, belonging to the institution), Markéta BÉBAROVÁ (203 Czech Republic, guarantor, belonging to the institution), Milena ŠIMURDOVÁ (203 Czech Republic, belonging to the institution) and Jiří ŠIMURDA (203 Czech Republic, belonging to the institution)

Edition

Frontiers in Physiology, LAUSANNE, FRONTIERS MEDIA SA, 2022, 1664-042X

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

30105 Physiology

Country of publisher

Switzerland

Confidentiality degree

není předmětem státního či obchodního tajemství

References:

URL

Impact factor

Impact factor: 4.000

RIV identification code

RIV/00216224:14110/22:00125820

Organization unit

Faculty of Medicine

DOI

http://dx.doi.org/10.3389/fphys.2022.837239

UT WoS

000802259800001

Keywords in English

sucrose; membrane capacitance; rat cardiomyocytes; new method; detubulation; t-tubules

Abstract

V originále

The transverse-axial tubular system (t-tubules) plays an essential role in excitation-contraction coupling in cardiomyocytes. Its remodelling is associated with various cardiac diseases. Numerous attempts were made to analyse characteristics essential for proper understanding of the t-tubules and their impact on cardiac cell function in health and disease. The currently available methodical approaches related to the fraction of the t-tubular membrane area produce diverse data. The widely used detubulation techniques cause irreversible cell impairment, thus, distinct cell samples have to be used for estimation of t-tubular parameters in untreated and detubulated cells. Our proposed alternative method is reversible and allows repetitive estimation of the fraction of t-tubular membrane (ft) in cardiomyocytes using short-term perfusion of the measured cell with a low-conductive isotonic sucrose solution. It results in a substantial increase in the electrical resistance of t-tubular lumen, thus, electrically separating the surface and t-tubular membranes. Using the whole-cell patch-clamp measurement and the new approach in enzymatically isolated rat atrial and ventricular myocytes, a set of data was measured and evaluated. The analysis of the electrical equivalent circuit resulted in the establishment of criteria for excluding measurements in which perfusion with a low conductivity solution did not affect the entire cell surface. As expected, the final average ft in ventricular myocytes (0.337 ± 0.017) was significantly higher than that in atrial myocytes (0.144 ± 0.015). The parameter ft could be estimated repetitively in a particular cell (0.345 ± 0.021 and 0.347 ± 0.023 in ventricular myocytes during the first and second sucrose perfusion, respectively). The new method is fast, simple, and leaves the measured cell intact. It can be applied in the course of experiments for which it is useful to estimate both the surface and t-tubular capacitance/area in a particular cell.

Links

MUNI/A/1133/2021, interní kód MU

Name: Od buňky k medicíně (Acronym: CELLVIEW)

Investor: Masaryk University

NU22-02-00348, research and development project

Name: Funkční hodnocení genetických variant u případů klinicky „skutečné“ idiopatické fibrilace komor: in vitro a in silico modelování s cílem odhalit arytmogenní mechanismus

Investor: Ministry of Health of the CR, Subprogram 1 - standard

Citovat

ŠVECOVÁ, Olga, Markéta BÉBAROVÁ, Milena ŠIMURDOVÁ and Jiří ŠIMURDA. Fraction of the T-Tubular Membrane as an Important Parameter in Cardiac Cellular Electrophysiology: A New Way of Estimation. Frontiers in Physiology. LAUSANNE: FRONTIERS MEDIA SA, 2022, vol. 13, May 2022, p. 1-12. ISSN 1664-042X. Available from: https://dx.doi.org/10.3389/fphys.2022.837239.

@article{1853626,
   author = {Švecová, Olga and Bébarová, Markéta and Šimurdová, Milena and Šimurda, Jiří},
   article_location = {LAUSANNE},
   article_number = {May 2022},
   doi = {http://dx.doi.org/10.3389/fphys.2022.837239},
   keywords = {sucrose; membrane capacitance; rat cardiomyocytes; new method; detubulation; t-tubules},
   language = {eng},
   issn = {1664-042X},
   journal = {Frontiers in Physiology},
   title = {Fraction of the T-Tubular Membrane as an Important Parameter in Cardiac Cellular Electrophysiology: A New Way of Estimation},
   url = {https://www.frontiersin.org/articles/10.3389/fphys.2022.837239/full},
   volume = {13},
   year = {2022}
}

TY  - JOUR
ID  - 1853626
AU  - Švecová, Olga - Bébarová, Markéta - Šimurdová, Milena - Šimurda, Jiří
PY  - 2022
TI  - Fraction of the T-Tubular Membrane as an Important Parameter in Cardiac Cellular Electrophysiology: A New Way of Estimation
JF  - Frontiers in Physiology
VL  - 13
IS  - May 2022
SP  - 1-12
EP  - 1-12
PB  - FRONTIERS MEDIA SA
SN  - 1664042X
KW  - sucrose
KW  - membrane capacitance
KW  - rat cardiomyocytes
KW  - new method
KW  - detubulation
KW  - t-tubules
UR  - https://www.frontiersin.org/articles/10.3389/fphys.2022.837239/full
N2  - The transverse-axial tubular system (t-tubules) plays an essential role in excitation-contraction coupling in cardiomyocytes. Its remodelling is associated with various cardiac diseases. Numerous attempts were made to analyse characteristics essential for proper understanding of the t-tubules and their impact on cardiac cell function in health and disease. The currently available methodical approaches related to the fraction of the t-tubular membrane area produce diverse data. The widely used detubulation techniques cause irreversible cell impairment, thus, distinct cell samples have to be used for estimation of t-tubular parameters in untreated and detubulated cells. Our proposed alternative method is reversible and allows repetitive estimation of the fraction of t-tubular membrane (ft) in cardiomyocytes using short-term perfusion of the measured cell with a low-conductive isotonic sucrose solution. It results in a substantial increase in the electrical resistance of t-tubular lumen, thus, electrically separating the surface and t-tubular membranes. Using the whole-cell patch-clamp measurement and the new approach in enzymatically isolated rat atrial and ventricular myocytes, a set of data was measured and evaluated. The analysis of the electrical equivalent circuit resulted in the establishment of criteria for excluding measurements in which perfusion with a low conductivity solution did not affect the entire cell surface. As expected, the final average ft in ventricular myocytes (0.337 ± 0.017) was significantly higher than that in atrial myocytes (0.144 ± 0.015). The parameter ft could be estimated repetitively in a particular cell (0.345 ± 0.021 and 0.347 ± 0.023 in ventricular myocytes during the first and second sucrose perfusion, respectively). The new method is fast, simple, and leaves the measured cell intact. It can be applied in the course of experiments for which it is useful to estimate both the surface and t-tubular capacitance/area in a particular cell.
ER  -

ŠVECOVÁ, Olga, Markéta BÉBAROVÁ, Milena ŠIMURDOVÁ and Jiří ŠIMURDA. Fraction of the T-Tubular Membrane as an Important Parameter in Cardiac Cellular Electrophysiology: A New Way of Estimation. \textit{Frontiers in Physiology}. LAUSANNE: FRONTIERS MEDIA SA, 2022, vol.~13, May 2022, p.~1-12. ISSN~1664-042X. Available from: https://dx.doi.org/10.3389/fphys.2022.837239.

Detailed Information on Publication Record