葛根总黄酮对离体家兔主动脉平滑肌的作用

EFFECT OF TOTAL FLAVONE IN RADIX PUERARIAE ON THE ISOLATED THORACAORTIC STRIPS IN RABBIT

目的研究葛根总黄酮（ＴＦＲＰ）对血管平滑肌的作用及其机制。②方法制备离体家兔胸主动脉螺旋条，采用去甲肾上腺素（ＮＡ）和高钾Ｋｒｅｂｓ液引起血管平滑肌（ＶＳＭ）收缩，观察ＴＦＲＰ的解痉作用；用酚妥拉明（Ｐｈｅｎ）或普奈洛尔（Ｐｒｏｐ）对标本进行预处理，观察两药对ＴＦＲＰ扩血管作用的影响；制作ＮＡ的剂量－效应曲线，研究ＴＦＲＰ对其影响。③结果ＴＦＲＰ４ｇ／Ｌ可使高钾和ＮＡ引起收缩的血管条明显松弛（ｔ＝４．３０４，６．８２３，Ｐ均＜０．０１），肌张力分别降低了４３％±１２％和５８％±１５％．在有或无Ｐｈｅｎ和Ｐｒｏｐ存在情况下，ＴＦＲＰ的扩血管作用差异无显著性（ｔ＝１．２８１，１．４４９，Ｐ均＞０．０５）。ＴＦＲＰ２ｇ／Ｌ可使ＮＡ的量－效曲线呈非平行性右移，并抑制ＮＡ收缩血管的最大效应。④结论ＴＦＲＰ对高钾和ＮＡ引起的血管痉挛有明显的松弛作用。

Objective To study the relaxing effect of total flavone in radix puerariae(TFRP) on vascular smooth muscle(VSM) and its mechanism. Methods The isolated thoracaortic strips of rabbit were prepared. The vasospasm evoked by noradrenaline(NA) and high K^+ were used to observe the spasmolytic actions of TFRP. Phentolamine(Phen) and propranolol(Prop) were used in advance to study the influences on the vasodilative action of TFRP. The doesresponse curves of NA were made to analyse the effect of TFRP. Results TFRP 4g/L obviously relaxed the vasospasm caused by high K+ and NA(t=4.034,6.823,P<0.01).The muscular tension were reduced 43%±12% and 58±15%.The vasodilative effects of TFRP didnt show marked difference in the absence or presence of Phen and Prop(t=1.281,1.449,P>0.05).TFRP 2g/L made the does response curve for NA shifted to right nonparallely, and depressed the maximal response of NA. Conclusion The results suggest that TFRP induces relaxing effect on vasospasm evoked by hight K+ and NA, and the mechanism is not related to the influence on α or β adrenoceptor.