花椒毒酚的药效学研究　Ⅰ抗心律失常作用

Studies on the pharmacodynamics of xanthotoxol I.Antiarrhythmic Effects

花椒毒酚（ｘａｎｔｈｏｔｏｘｏｌ，ＸＴ）是从蛇床子乙醇提取物中分离出的一种香豆素。ＸＴ对氯仿诱发的小鼠室颤、氯化钙诱发的大鼠室颤均有明显的预防作用，对乌头碱诱发的大鼠心律失常有显著的治疗效果，且能明显提高兔心室电致颤阈。此外，ＸＴ还能降低蟾蜍离体坐骨神经干的动作电位振幅。这些均表明ＸＴ有抗心律失常的作用。ＸＴ的小鼠ｉｖＬＤ＿（５０）为４７．０ｍｇ·ｋｇ￣（－１）。

Xanthotoxol(XT) is a coumarin isolated from ethyl alcohol extracts of the fruits of cnidium monnieri(L.) Cusson.It is not only effective in preventing ventricular fibrillation induced by chloroform in mice or by calcium chloride in rats, but is effective in treating arrhythmia induced by aconitine in rats.It can raise the threthold of ventricular fibrillation induced by electrical stimulation in rabbits. Furthermore,XT can inhibit the action potential amplitude of isolated sciatic, nerves in toads. These results indicate that XT possesses antiarrhythmic effects.The acute LD_(50) of XT in mice is iv 47.0mg·kg￣(-1).