Effects of docosahexaenoic acid on sodium channel current and transient outward potassium channel current in rat ventricular myocytes
10.3760/cma.j.issn.0253-3758.2011.05.015
- VernacularTitle:二十二碳六烯酸对大鼠心室肌细胞钠通道和瞬时外向钾通道的影响
- Author:
Li-Hong LAI
1
;
Ping-Shuan DONG
;
Zhuan-Zhen LI
;
Zhi-Juan LI
;
Ru-Xing WANG
;
Wen-Ping JIANG
Author Information
1. 河南科技大学附属第一医院
- Keywords:
Sodium channels;
Potassium channels;
Patch-clamp techniques;
Docosahexaenoic acid
- From:
Chinese Journal of Cardiology
2011;39(5):451-456
- CountryChina
- Language:Chinese
-
Abstract:
Objective To investigate the effects of docosahexaenoic acid(DHA)on sodium channel current(INa)and transient outward potassium channel current(Ito)in rat ventricular myocytes and to evaluate potential anti-arrhythmic mechanisms of DHA.Methods INa and Ito of individual ventricular myocytes were recorded by patch-clamp technique in whole-cell configuration at room temperature.Effects of DHA at various concentrations(0,20,40,60,80,100 and 120 μmol/L)on INa and Ito were observed.Results (1) INa was blocked in a concentration-dependent manner by DHA,stably inactivated curves were shifted to the left,and recover time from inactivation was prolonged while stably activated curves were not affected by DHA.At-30 mV,INa was blocked to(1.51 ±1.32)%,(21.13±4.62)%,(51.61 ±5.73)%,(67.62 ±6.52)%,(73.49±7.59)%and(79.95±7.62)%in the presence of above DHA concentrations(all P<0.05,n=20),and half-effect concentration(EC50)of DHA on INa was(47.91±1.57)μmol/L(2) Ito were also blocked in a concentration-dependent manner by DHA,stably inactivated curves were shifted to the left,and recover time from inactivation was prolonged with increasing concentrations of DHA,and stably activated curves were not affected by DHA.At+70 mV,Ito was blocked to(2.61 ±0.26)%,(21.79±4.85)%,(63.11 ±6.57)%,(75.52 ±7.26)%,(81.82 ±7.63)%and(84.33±8.25)%,respectively,in the presence of above DHA concentrations(all P<0.05,n=20),and the EC50 of DHA on Ito was(49.11±2.68)μmol/1.Conclusion The blocking effects of DHA on APD and Ito may serve as one of the anti-arrhythmia mechanisms of DHA.
