Background nonselective cationic current and the resting membrane potential in rabbit aorta endothelial cells

S. J. Park, Y. C. Kim, S. H. Suh, H. Rhim, J. H. Sim, Sungjoon Kim, Insuk So, K. W. Kim

Research output: Contribution to journalArticleResearchpeer-review

3 Citations (Scopus)

Abstract

The ion channel conductances that regulate the membrane potential was investigated by using a perforated patch-clamp technique in rabbit aorta endothelial cells (RAECs). The whole-cell current/voltage (I-V) relation showed a slight outward rectification under physiological ionic conditions. The resting membrane potential was -23.3±1.1 mV (mean±SEM, n=19). The slope conductances at the potentials of -80 and 50 mV were 31.0±4.0 and 62.8±7.1 pS pF -1 , respectively (n=15). Changes in the extracellular and intracellular Cl - concentrations did not affect the reversal potential on I-V curves. The background nonselective cationic (NSC) current was isolated after the K + current was suppressed. The relative permeabilities calculated from the changes in reversal potentials using the constant-field theory were P K :P Cs :P Na :P Li =1:0.87:0.40:0.27 and P Cs: :P Ca =1:0.21. Increases in the external Ca 2+ decreased the background NSC current in a dose-dependent manner. The concentration for half block by Ca 2+ was 1.1±0.3 mM (n=7). Through the continuous recording of the membrane potential in a current-clamp mode, it was found that the background NSC conductance is the major determinant of resting membrane potential. Taken together, it could be concluded that the background NSC channels function as the major determinant for the resting membrane potential and can be responsible for the background Ca 2+ entry pathway in freshly isolated RAECs.

Original languageEnglish
Pages (from-to)635-643
Number of pages9
JournalJapanese Journal of Physiology
Volume50
Issue number6
DOIs
StatePublished - 1 Dec 2000

Fingerprint

Membrane Potentials
Aorta
Endothelial Cells
Rabbits
Patch-Clamp Techniques
Ion Channels
Permeability

Keywords

  • Background nonselective cationic current
  • Rabbit aorta endothelial cell
  • Relative permeability
  • Resting membrane potential

Cite this

Park, S. J. ; Kim, Y. C. ; Suh, S. H. ; Rhim, H. ; Sim, J. H. ; Kim, Sungjoon ; So, Insuk ; Kim, K. W. / Background nonselective cationic current and the resting membrane potential in rabbit aorta endothelial cells. In: Japanese Journal of Physiology. 2000 ; Vol. 50, No. 6. pp. 635-643.
@article{4bb3ba5982ab4e4a8f75be1da61a7530,
title = "Background nonselective cationic current and the resting membrane potential in rabbit aorta endothelial cells",
abstract = "The ion channel conductances that regulate the membrane potential was investigated by using a perforated patch-clamp technique in rabbit aorta endothelial cells (RAECs). The whole-cell current/voltage (I-V) relation showed a slight outward rectification under physiological ionic conditions. The resting membrane potential was -23.3±1.1 mV (mean±SEM, n=19). The slope conductances at the potentials of -80 and 50 mV were 31.0±4.0 and 62.8±7.1 pS pF -1 , respectively (n=15). Changes in the extracellular and intracellular Cl - concentrations did not affect the reversal potential on I-V curves. The background nonselective cationic (NSC) current was isolated after the K + current was suppressed. The relative permeabilities calculated from the changes in reversal potentials using the constant-field theory were P K :P Cs :P Na :P Li =1:0.87:0.40:0.27 and P Cs: :P Ca =1:0.21. Increases in the external Ca 2+ decreased the background NSC current in a dose-dependent manner. The concentration for half block by Ca 2+ was 1.1±0.3 mM (n=7). Through the continuous recording of the membrane potential in a current-clamp mode, it was found that the background NSC conductance is the major determinant of resting membrane potential. Taken together, it could be concluded that the background NSC channels function as the major determinant for the resting membrane potential and can be responsible for the background Ca 2+ entry pathway in freshly isolated RAECs.",
keywords = "Background nonselective cationic current, Rabbit aorta endothelial cell, Relative permeability, Resting membrane potential",
author = "Park, {S. J.} and Kim, {Y. C.} and Suh, {S. H.} and H. Rhim and Sim, {J. H.} and Sungjoon Kim and Insuk So and Kim, {K. W.}",
year = "2000",
month = "12",
day = "1",
doi = "10.2170/jjphysiol.50.635",
language = "English",
volume = "50",
pages = "635--643",
journal = "Japanese Journal of Physiology",
issn = "0021-521X",
publisher = "Physiological Society of Japan",
number = "6",

}

Background nonselective cationic current and the resting membrane potential in rabbit aorta endothelial cells. / Park, S. J.; Kim, Y. C.; Suh, S. H.; Rhim, H.; Sim, J. H.; Kim, Sungjoon; So, Insuk; Kim, K. W.

In: Japanese Journal of Physiology, Vol. 50, No. 6, 01.12.2000, p. 635-643.

Research output: Contribution to journalArticleResearchpeer-review

TY - JOUR

T1 - Background nonselective cationic current and the resting membrane potential in rabbit aorta endothelial cells

AU - Park, S. J.

AU - Kim, Y. C.

AU - Suh, S. H.

AU - Rhim, H.

AU - Sim, J. H.

AU - Kim, Sungjoon

AU - So, Insuk

AU - Kim, K. W.

PY - 2000/12/1

Y1 - 2000/12/1

N2 - The ion channel conductances that regulate the membrane potential was investigated by using a perforated patch-clamp technique in rabbit aorta endothelial cells (RAECs). The whole-cell current/voltage (I-V) relation showed a slight outward rectification under physiological ionic conditions. The resting membrane potential was -23.3±1.1 mV (mean±SEM, n=19). The slope conductances at the potentials of -80 and 50 mV were 31.0±4.0 and 62.8±7.1 pS pF -1 , respectively (n=15). Changes in the extracellular and intracellular Cl - concentrations did not affect the reversal potential on I-V curves. The background nonselective cationic (NSC) current was isolated after the K + current was suppressed. The relative permeabilities calculated from the changes in reversal potentials using the constant-field theory were P K :P Cs :P Na :P Li =1:0.87:0.40:0.27 and P Cs: :P Ca =1:0.21. Increases in the external Ca 2+ decreased the background NSC current in a dose-dependent manner. The concentration for half block by Ca 2+ was 1.1±0.3 mM (n=7). Through the continuous recording of the membrane potential in a current-clamp mode, it was found that the background NSC conductance is the major determinant of resting membrane potential. Taken together, it could be concluded that the background NSC channels function as the major determinant for the resting membrane potential and can be responsible for the background Ca 2+ entry pathway in freshly isolated RAECs.

AB - The ion channel conductances that regulate the membrane potential was investigated by using a perforated patch-clamp technique in rabbit aorta endothelial cells (RAECs). The whole-cell current/voltage (I-V) relation showed a slight outward rectification under physiological ionic conditions. The resting membrane potential was -23.3±1.1 mV (mean±SEM, n=19). The slope conductances at the potentials of -80 and 50 mV were 31.0±4.0 and 62.8±7.1 pS pF -1 , respectively (n=15). Changes in the extracellular and intracellular Cl - concentrations did not affect the reversal potential on I-V curves. The background nonselective cationic (NSC) current was isolated after the K + current was suppressed. The relative permeabilities calculated from the changes in reversal potentials using the constant-field theory were P K :P Cs :P Na :P Li =1:0.87:0.40:0.27 and P Cs: :P Ca =1:0.21. Increases in the external Ca 2+ decreased the background NSC current in a dose-dependent manner. The concentration for half block by Ca 2+ was 1.1±0.3 mM (n=7). Through the continuous recording of the membrane potential in a current-clamp mode, it was found that the background NSC conductance is the major determinant of resting membrane potential. Taken together, it could be concluded that the background NSC channels function as the major determinant for the resting membrane potential and can be responsible for the background Ca 2+ entry pathway in freshly isolated RAECs.

KW - Background nonselective cationic current

KW - Rabbit aorta endothelial cell

KW - Relative permeability

KW - Resting membrane potential

UR - http://www.scopus.com/inward/record.url?scp=0034451836&partnerID=8YFLogxK

U2 - 10.2170/jjphysiol.50.635

DO - 10.2170/jjphysiol.50.635

M3 - Article

VL - 50

SP - 635

EP - 643

JO - Japanese Journal of Physiology

JF - Japanese Journal of Physiology

SN - 0021-521X

IS - 6

ER -