摘要
用离体家兔气管平滑肌标本，观察白花前胡甲素对乙酰胆碱及高钾诱发标本收缩反应的松驰作用和标本对乙酰胆碱及ＣａＣｌ２的量效关系的影响。同时研究二药对标本在无钙液中加入ＣａＣｌ２时单剂量乙酰胆碱诱发标本二个时相收缩反应的影响。同时研究二药对标本在无钙液中和加入ＣａＣｌ２时单剂量乙酰胆碱诱发标本二个时相收缩反应的影响，并与维拉帕米进行对比。结果表明，白花前胡甲素的作用与维拉帕米相似，对高钾诱发的气管平滑肌收缩反应有显著抑制作用，使标本对乙酰胆碱和ＣａＯｌ２的量效反应曲线右移，最大反应降低，显著抑制乙酰胆碱引起的第一时相依内Ｃａ２＋性收缩，对受体启动依外Ｃａ２－性收缩作用无明显影响。实验结果提示，白花前胡甲素对气管平滑肌的松弛作用与抑制电位依赖性钙通道和细胞内Ｃａ２＋释放作用有关。
Praeruptorin A(PdIa)is an effective component extracted from Chinese
traditional herb“ Qian-Hu”. We studied its ettects on the tracheal smooth muscle isolated
from rabbits. These effects werecompared with those exerted by verapamil.Both were similar.
PdIa relaxed the precontraction inducedby depolarized concentration of KCl(high K)more
effectively than that by acetylcholine(ACh,10μmol/L).The dose-response curve to CaCl2 and
ACh were shifted to the right and the maximal re-sponse was depressed by PdIa.PdIa inhibited
the contractile response to ACh(10μmol/L)in Ca-freemedium more significantly than the
subsequent contractile response followed in addition of CaCl2 2.0mmol/L. On the other hand,the
effects of verapamil( 0.5μmol/L)were qualitatively similar to thoseof PdIa. These results
suggested that the mechanism of the relaxing effect of PdIa on tracheal smoothmuscle of
rabbits was through blocking the potential-dependent Ca channel(PDC)and inhibiting the
re-lease of Ca from intracellular Ca-store.
出处
《中国医科大学学报》
CAS
CSCD
1994年第6期549-552,共4页
Journal of China Medical University
