摘要
本文用核素45Ca示踪法观察了毛冬青甲素对兔主动脉平滑肌钙离子跨膜流动的影响。结果显示:毛冬青甲素(10^(-4)mol/L)对正常营养液的主动脉平滑肌钙离子内流和外流均无明显影响(p>0.3),但对高钾(140mmol/L)或去甲肾上腺素(10^(-5)mol/L)引起的主动脉平滑肌钙离子内流却有抑制作用(p<0.01)。结果提示毛冬青甲素对平滑肌细胞膜上的电位依赖性钙通道和受体操纵性钙通道均有拮抗作用。
Effect of Ilexonin A (IA) on Ca^(++) influxes in the rabbit aorta was studied with radioactive ^(45)Ca. The result showed that either Ca^(++) influx or Ca^(++) efflux of rabbit aorta induced by IA itself in the normal medium was insignificantly different from the normal control. But it was found that IA inhibited Ca^(++) influx stimulated by alpha adrenoceptor activation (NE 10^(-5) M) or by high-K^+ (140mM) depolarization (significantly different from corresponding control). It suggestes that IA blockade to Ca^(++) channels is correlated with both the potential-dependent channels and the receptor operated channels in vascular smooth muscle.
关键词
毛冬青
主动脉
药理学
ILEX PUBESCENS/Pharmacodynamics AORTA/Drug effect MUSCLE. SMOOTH. VASCULAR/Drug effect ION CHANNELS/Drug effect
