摘要
研究丁咯地尔(BUF)对豚鼠乳头肌快反应动作电位(AP)的影响。方法采用细胞内微电极技术 ,观察不同浓度BUF对AP的影响。结果各浓度BUF使动作电位幅度(APA)明显降低 ,使APD 30,APD 50缩短 ;BUF10-4M和10-3 使APD 90 也明显缩短。5×10-3M使AP消失之后 ,还使静息电位(RP)绝对值继续降低。结论(1)BUF对豚鼠乳头肌Ca2 + 、Na +通道有阻滞作用 ;对K +通道的影响较复杂。(2)BUF使豚鼠乳头肌对电刺激的兴奋性降低。(3)BUF对AP的作用是可逆的。
Aim To study the effects of Buflomedil hydrochloride (BUF) on the fast action potential (AP) of isolated guinea pig papillary muscles. Methods Itracellular microelectrode technique was used to investigate the effects of different BUF concentrations on AP. Results Different concentrations of BUF significantly reduced the amplitude of action potential (APA) and shortened the action potential duration (APD) on the levels of APD 30 and APD 50 APD 90 was also evidently shortened by BUF 10-4 M and 10-3M. The onset of the action was relatively delayed by BUF 10-4M. BUF 10-3M and 5×10-3M exerted their actions more quickly and induced a concentration-dependent decrease in the excitability of papillary muxcles. BUF 5×10-3 M continued decreasing the absolute value of resting potential (RP) after it abolished AP. Conclusions (1) BUF inhibit Ca2+, Na+ channels of guinea pig papillary muscles. The action mechanisms of BUF on K+ channels are complicated. (2) BUF could reduce the excitability of guinea pig papillary muscles to electrical field stimulation. (3) The inhibitory effects of BUF on AP are reversible.
关键词
丁咯地尔
豚鼠
乳头肌
快反应动作电位
血管扩张药
buflomedil hydrochloride (BUF)
guinea pig
papillary muscle
action potential (AP)
