KMID : 0043320170400101135
|
|
Archives of Pharmacal Research 2017 Volume.40 No. 10 p.1135 ~ p.1145
|
|
Magnesium isoglycyrrhizinate inhibits L-type Ca2+ channels, Ca2+ transients, and contractility but not hERG K+ channels
|
|
Lin Yue
Zhang Yuan Yuan Song Qiong Tao Song Tao Han Xue Zhang Ying Zhang Xuan Chu Xi Zhang Feng Hua Chu Li Zhang Jian Ping
|
|
Abstract
|
|
|
To explore the cardiovascular protective effects of Magnesium isoglycyrrhizinate (MI), especially the underlying cellular mechanisms related to L-type calcium channels and myocardial contractility, and to examine the effects of MI on hERG K+ current expressed in HEK293 cells. We used the whole-cell patch clamp technique, video-based edge detection and dual excitation fluorescence photomultiplier systems to explore the effect of MI on L-type Ca2+ currents (ICa-L) and cell contraction in rat cardiomyocytes. We also examined the rapidly activating delayed rectifier potassium current (IKr) expressed in HEK293 cells using a perforated patch clamp. MI inhibited ICa-L in a dose-dependent manner, with a half-maximal inhibitory concentration (IC50) of 0.22 mg/ml, and the maximal inhibitory effect was 61.10 ¡¾ 0.59%. MI at a concentration of 0.3 mg/ml reduced cell shortening by 24.12 ¡¾ 3.97% and the peak value of the Ca2+ transient by 36.54 ¡¾ 4.96%. MI had no significant influence on hERG K+ channels expressed in HEK293 cells at all test potentials. MI exerts protective effects on the heart via the inhibition of ICa-L and cell shortening in rat cardiomyocytes. However, MI had no significant influence on IKr; thus, MI may exert cardioprotective effects without causing drug-induced long QT syndrome.
|
|
KEYWORD
|
|
Magnesium isoglycyrrhizinate, L-type Ca2+ currents, Myocyte shortening, Ca2+ transient hERG K+ channels, Rat cardiomyocyte
|
|
FullTexts / Linksout information
|
|
|
|
Listed journal information
|
|
|