摘要
三七中人参三醇甙(PTS)2.5μg/ml及5.0μg/ml均能明显延长羊心浦氏纤维动作电位时程(APD)包括APD_(30),APD_(50),APD_(90),对动作电位幅度(APA)无明显影响。双微电极法电压钳实验证明,PTS能明显抑制羊心浦氏纤维延迟整流钾电流(I_x)的峰值,且此种抑制作用呈时间及剂量依赖性。揭示PTS通过阻滞延迟整流钾通道而延长APD。
The electrophysiological effects of PTS in sheep cardiac Purkinje fibers were studied. PTS was shown to increase the duration of action potential (APD_(30), APD_(50) and APD_(90)) at the concentrations of 2. 5μg/ml and 5. 0μg/ml. However, the amplitude of action potential (APA) remained unchanged. The result of using double microelectrode voltage clamp method showed that PTS (1. 25～10. 0μg/ml) depressed the delayed (outward) rectifier current (Ⅰ_x) in time-and dosedependent manners, when the holding potential was held at±20 mV, the command potential was held at±10 mV, 0.2 Hz and the clamping time at 1～1.5s.It may be concluded that the effect of PTS on APD is mainly related to blocking the delayed rectifier potassium channel.
出处
《药学学报》
CAS
CSCD
北大核心
1993年第2期81-84,共4页
Acta Pharmaceutica Sinica
基金
国家自然科学基金 NO 3880739
关键词
三七
人参三醇甙
动作电位
钾通道
Panax notoginseng
Panaxatriol saponins
Action potential
Delayed rectifier current
Potassium channel
