Hydrogen peroxide modulates electrophysiological characteristics of left atrial myocytes

Shih Yu Huang, Yen Yu Lu, Yao Chang Chen, Wei Ta Chen, Yung Kuo Lin, Shih Ann Chen, Yi Jen Chen

Research output: Contribution to journalArticle

4 Citations (Scopus)

Abstract

Background: Oxidative stress plays an important role in the pathophysiology of atrial fibrillation (AF). The hydrogen peroxide (H2O2) mainly underlies the cellular oxidative stress and free radicals. Left atrium (LA) is the most important AF substrate. However, the effects of H 2O2 on the action potential (AP) and ionic currents in LA myocytes have not been fully elucidated. Methods: The whole-cell patch clamp was used to investigate the APs and ionic currents of L-type calcium current (ICa-L), transient outward currents (Ito), ultra-rapid delayed rectifier potassium current (IKur), delayed rectifier potassium currents (IK), inward rectifier potassium current (I K1), and sodium-calcium exchanger (NCX) before and after H 2O2 (100 μM) in isolated rabbit LA myocytes. Results: H2O2 (100 μM) shortened by 50% (from40 ± 7 to 21 ± 5ms) and 90% the AP duration (from 95 ± 12 to 74 ± 11 ms) in LA myocytes (n = 9), but did not change the resting membrane potentials. The H2O2 (100 μM) decreased Ito, but increased IKur and IK. H2O2 (100 μM) also reduced the ICa-L and the reverse mode NCX. However, H2O2 (100 μM) did not change IK1. Conclusions: H2O2 directly modulated the APmorphology and ionic currents in LAmyocytes, which may contribute to the genesis of AF in oxidative stress.

Original languageEnglish
Pages (from-to)38-45
Number of pages8
JournalActa Cardiologica Sinica
Volume30
Issue number1
Publication statusPublished - 2014

Fingerprint

Heart Atria
Muscle Cells
Hydrogen Peroxide
Atrial Fibrillation
Potassium
Oxidative Stress
Action Potentials
Sodium-Calcium Exchanger
Membrane Potentials
Free Radicals
Rabbits
Calcium

Keywords

  • Action potential
  • Ionic current
  • Oxidative stress

ASJC Scopus subject areas

  • Cardiology and Cardiovascular Medicine

Cite this

Hydrogen peroxide modulates electrophysiological characteristics of left atrial myocytes. / Huang, Shih Yu; Lu, Yen Yu; Chen, Yao Chang; Chen, Wei Ta; Lin, Yung Kuo; Chen, Shih Ann; Chen, Yi Jen.

In: Acta Cardiologica Sinica, Vol. 30, No. 1, 2014, p. 38-45.

Research output: Contribution to journalArticle

Huang, Shih Yu ; Lu, Yen Yu ; Chen, Yao Chang ; Chen, Wei Ta ; Lin, Yung Kuo ; Chen, Shih Ann ; Chen, Yi Jen. / Hydrogen peroxide modulates electrophysiological characteristics of left atrial myocytes. In: Acta Cardiologica Sinica. 2014 ; Vol. 30, No. 1. pp. 38-45.
@article{00c2a26dd8eb4db192dc4cc90ee9ec13,
title = "Hydrogen peroxide modulates electrophysiological characteristics of left atrial myocytes",
abstract = "Background: Oxidative stress plays an important role in the pathophysiology of atrial fibrillation (AF). The hydrogen peroxide (H2O2) mainly underlies the cellular oxidative stress and free radicals. Left atrium (LA) is the most important AF substrate. However, the effects of H 2O2 on the action potential (AP) and ionic currents in LA myocytes have not been fully elucidated. Methods: The whole-cell patch clamp was used to investigate the APs and ionic currents of L-type calcium current (ICa-L), transient outward currents (Ito), ultra-rapid delayed rectifier potassium current (IKur), delayed rectifier potassium currents (IK), inward rectifier potassium current (I K1), and sodium-calcium exchanger (NCX) before and after H 2O2 (100 μM) in isolated rabbit LA myocytes. Results: H2O2 (100 μM) shortened by 50{\%} (from40 ± 7 to 21 ± 5ms) and 90{\%} the AP duration (from 95 ± 12 to 74 ± 11 ms) in LA myocytes (n = 9), but did not change the resting membrane potentials. The H2O2 (100 μM) decreased Ito, but increased IKur and IK. H2O2 (100 μM) also reduced the ICa-L and the reverse mode NCX. However, H2O2 (100 μM) did not change IK1. Conclusions: H2O2 directly modulated the APmorphology and ionic currents in LAmyocytes, which may contribute to the genesis of AF in oxidative stress.",
keywords = "Action potential, Ionic current, Oxidative stress",
author = "Huang, {Shih Yu} and Lu, {Yen Yu} and Chen, {Yao Chang} and Chen, {Wei Ta} and Lin, {Yung Kuo} and Chen, {Shih Ann} and Chen, {Yi Jen}",
year = "2014",
language = "English",
volume = "30",
pages = "38--45",
journal = "Acta Cardiologica Sinica",
issn = "1011-6842",
publisher = "Republic of China Society of Cardiology",
number = "1",

}

TY - JOUR

T1 - Hydrogen peroxide modulates electrophysiological characteristics of left atrial myocytes

AU - Huang, Shih Yu

AU - Lu, Yen Yu

AU - Chen, Yao Chang

AU - Chen, Wei Ta

AU - Lin, Yung Kuo

AU - Chen, Shih Ann

AU - Chen, Yi Jen

PY - 2014

Y1 - 2014

N2 - Background: Oxidative stress plays an important role in the pathophysiology of atrial fibrillation (AF). The hydrogen peroxide (H2O2) mainly underlies the cellular oxidative stress and free radicals. Left atrium (LA) is the most important AF substrate. However, the effects of H 2O2 on the action potential (AP) and ionic currents in LA myocytes have not been fully elucidated. Methods: The whole-cell patch clamp was used to investigate the APs and ionic currents of L-type calcium current (ICa-L), transient outward currents (Ito), ultra-rapid delayed rectifier potassium current (IKur), delayed rectifier potassium currents (IK), inward rectifier potassium current (I K1), and sodium-calcium exchanger (NCX) before and after H 2O2 (100 μM) in isolated rabbit LA myocytes. Results: H2O2 (100 μM) shortened by 50% (from40 ± 7 to 21 ± 5ms) and 90% the AP duration (from 95 ± 12 to 74 ± 11 ms) in LA myocytes (n = 9), but did not change the resting membrane potentials. The H2O2 (100 μM) decreased Ito, but increased IKur and IK. H2O2 (100 μM) also reduced the ICa-L and the reverse mode NCX. However, H2O2 (100 μM) did not change IK1. Conclusions: H2O2 directly modulated the APmorphology and ionic currents in LAmyocytes, which may contribute to the genesis of AF in oxidative stress.

AB - Background: Oxidative stress plays an important role in the pathophysiology of atrial fibrillation (AF). The hydrogen peroxide (H2O2) mainly underlies the cellular oxidative stress and free radicals. Left atrium (LA) is the most important AF substrate. However, the effects of H 2O2 on the action potential (AP) and ionic currents in LA myocytes have not been fully elucidated. Methods: The whole-cell patch clamp was used to investigate the APs and ionic currents of L-type calcium current (ICa-L), transient outward currents (Ito), ultra-rapid delayed rectifier potassium current (IKur), delayed rectifier potassium currents (IK), inward rectifier potassium current (I K1), and sodium-calcium exchanger (NCX) before and after H 2O2 (100 μM) in isolated rabbit LA myocytes. Results: H2O2 (100 μM) shortened by 50% (from40 ± 7 to 21 ± 5ms) and 90% the AP duration (from 95 ± 12 to 74 ± 11 ms) in LA myocytes (n = 9), but did not change the resting membrane potentials. The H2O2 (100 μM) decreased Ito, but increased IKur and IK. H2O2 (100 μM) also reduced the ICa-L and the reverse mode NCX. However, H2O2 (100 μM) did not change IK1. Conclusions: H2O2 directly modulated the APmorphology and ionic currents in LAmyocytes, which may contribute to the genesis of AF in oxidative stress.

KW - Action potential

KW - Ionic current

KW - Oxidative stress

UR - http://www.scopus.com/inward/record.url?scp=84898427928&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84898427928&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:84898427928

VL - 30

SP - 38

EP - 45

JO - Acta Cardiologica Sinica

JF - Acta Cardiologica Sinica

SN - 1011-6842

IS - 1

ER -