二十二碳六烯酸对大鼠心室肌细胞离子通道的调节作用。

Regulatory functions of docosahexaenoic acid on ion channels in rat ventricular myocytes.

机构信息

Department of Cardiology, First Affiliated Hospital of Henan University of Science and Technology, Luoyang, China.

出版信息

Eur Rev Med Pharmacol Sci. 2013 Oct;17(19):2632-8.

Abstract

OBJECTIVE

The aim of this study was to study the regulatory functions of docosahexaenoic acid (DHA) on resting potential (RP), action potential duration (APD), delayed rectifier potassium current (Ik), and inwardly rectifier potassium current (Ik1) in rat ventricular myocytes, and analyze the related anti-arrhythmia mechanism.

MATERIALS AND METHODS

Rat ventricular myocytes were isolated by enzyme digestion method. RP, APD, Ik and Ik1 in individual ventricular myocytes were recorded by patch-clamp technique with whole-cell configuration. Effects of DHA with various concentrations (0, 20, 40, 60, 80, 100 and 120 mmol/L, respectively) on RP, AP, Ik and Ik1 were investigated.

RESULTS

There was no statistical difference of RP with different DHA concentrations (p > 0.05, n = 20), and the 25%, 50% and 90% of APD (APD25, APD50, and APD90) were gradually prolonged with increase of DHA concentration, respectively (p < 0.05, n = 20). IK gradually blocked and the I-V curve was downward shifted, according to increase of DHA concentration (p < 0.05, n = 20). The DHA half effect concentration (EC50) was 47.52 ± 2.32 µmol/L. With increasing DHA concentration, the steady-state inactivation curve shifted to left, and the recovery curve shifted to right. DHA had no significant effect on IK1 (p > 0.05, n = 20).

CONCLUSIONS

DHA has regulatory functions on RP, APD, Ik and Ik1 in rat ventricular myocytes, which may be one of the related antiarrhythmic mechanisms.

摘要

目的

本研究旨在探讨二十二碳六烯酸（DHA）对大鼠心室肌细胞静息电位（RP）、动作电位时程（APD）、延迟整流钾电流（Ik）和内向整流钾电流（Ik1）的调节作用，并分析其相关的抗心律失常机制。

材料与方法

采用酶消化法分离大鼠心室肌细胞。采用全细胞膜片钳技术的细胞贴附式记录单个心室肌细胞的 RP、APD、Ik 和 Ik1。观察不同浓度（0、20、40、60、80、100 和 120mmol/L）DHA 对 RP、AP、Ik 和 Ik1 的影响。

结果

不同浓度 DHA 对 RP 无统计学差异（p>0.05，n=20），而 APD25、APD50 和 APD90 分别随 DHA 浓度的增加而逐渐延长（p<0.05，n=20）。随着 DHA 浓度的增加，Ik 逐渐阻滞，I-V 曲线向下移位（p<0.05，n=20）。DHA 的半数效应浓度（EC50）为 47.52±2.32µmol/L。随着 DHA 浓度的增加，稳态失活曲线向左移位，恢复曲线向右移位。DHA 对 Ik1 无明显影响（p>0.05，n=20）。