J 2022

A new approach to the determination of tubular membrane capacitance: passive membrane electrical properties under reduced electrical conductivity of the extracellular solution

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

Basic information

Original name

A new approach to the determination of tubular membrane capacitance: passive membrane electrical properties under reduced electrical conductivity of the extracellular solution

Authors

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

Edition

Pflügers Archiv - European Journal of Physiology, Heidelberg, Springer, 2022, 0031-6768

Other information

Language

English

Type of outcome

Článek v odborném periodiku

Field of Study

30105 Physiology

Country of publisher

Germany

Confidentiality degree

není předmětem státního či obchodního tajemství

References:

Impact factor

Impact factor: 4.500

RIV identification code

RIV/00216224:14110/22:00127149

Organization unit

Faculty of Medicine

UT WoS

000873954800001

Keywords in English

Cardiomyocyte; Tubular system; Tubular membrane capacitance; Novel method; Sucrose

Tags

International impact, Reviewed
Změněno: 15/11/2022 08:11, Mgr. Tereza Miškechová

Abstract

V originále

The transverse-axial tubular system (tubular system) of cardiomyocytes plays a key role in excitation-contraction coupling. To determine the area of the tubular membrane in relation to the area of the surface membrane, indirect measurements through the determination of membrane capacitances are currently used in addition to microscopic methods. Unlike existing electrophysiological methods based on an irreversible procedure (osmotic shock), the proposed new approach uses a reversible short-term intermittent increase in the electrical resistance of the extracellular medium. The resulting increase in the lumen resistance of the tubular system makes it possible to determine separate capacitances of the tubular and surface membranes. Based on the analysis of the time course of the capacitive current, computational relations were derived to quantify the elements of the electrical equivalent circuit of the measured cardiomyocyte including both capacitances. The exposition to isotonic low-conductivity sucrose solution is reversible which is the main advantage of the proposed approach allowing repetitive measurements on the same cell under control and sucrose solutions. Experiments on rat ventricular cardiomyocytes (n = 20) resulted in the surface and tubular capacitance values implying the fraction of tubular capacitance/area of 0.327 +/- 0.018. We conclude that the newly proposed method provides results comparable to the data obtained by the currently used detubulation method and, in addition, by being reversible, allows repeated evaluation of surface and tubular membrane parameters on the same 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