甲基黄酮醇胺对离体豚鼠气管的作用

本文比较性研究甲基黄酮醇胺盐酸盐（ＭＦＡ），三氟拉嗪（Ｔｒｉ），维拉帕米（Ｖｅｒ），氨茶碱（Ａｍｉ）和异丙肾上腺素（Ｉｓｏ）对豚鼠离体气管的舒张作用．ＭＦＡ（０．１－０．３ｍｍｏｌ·Ｌ－１）时间依赖性舒张ＫＣｌ诱导的气管平滑肌收缩。低于０．１ｍｍｏｌ·Ｌ－１时ＭＦＡ对ＫＣｌ诱导的收缩仅有轻微作用，却使Ｉｓｏ和Ａｍｉ的浓度舒张曲线明显向左上移动。ＭＦＡ，Ｖｅｒ，Ｔｒｉ使ＣａＣｌ２量效曲线向右下移，ｐＤ２值分别为：５．０±ｓ０．５，６．４±ｓ０．８，５．０±ｓ０．６．ＭＦＡ，Ｖｅｒ，Ｔｒｉ，Ａｍｉ剂量依赖性抑制次大量生理激动剂所致的收缩，其作用强度顺序为：Ｔｒｉ＞Ｖｅｒ＝ＭＦＡ＞Ａｍｉ．提示ＭＦＡ具有非竞争性钙拮抗作用，其作用方式与Ｔｒｉ相似。与Ａｍｉ相比、ＭＦＡ是一个较强的主气管扩张剂，并与Ａｍｉ，Ｉｓｏ具有明显的协同舒张支气管作用。

Effect of methylflavonolamine hydrochloride on theisolated trachea in guinea-pig

The effects of methylflavonolamine(MFA) on bronchoactive agents-induced contractionsand bronchodilators-induced relaxations were studiedon guinea-pig isolated trachea and compared withthat of verapamil (Ver) and trifluoperazine (Tri). At0.1-0.3 mmol · L-1, MFA timedependently relaxedthe contraction induced by 40 mmol · L 1 KCl. Atconcentration below 0. 1 mmol · L -1 , MFA produced anegligible relaxation on KCl-induced contraction, butsignificantly shifted the isoprenaline (lso) andaminophylline (Ami) concentration-relaxation curvesupwards to the left. MFA. Ver, Tri and Ami inhibitedthe contractions induced by submaximal concentra-tions of physiologic agonists. The inhibitory potencyorder was Tri> Ver = MFA > Ami. MFA. Ver and Trishifted CaCl2 cumulative curves downwards to theright with the pDz values 5.0± s 0.5, 6.4± s 0.8 and5.0± s 0.6, respectively. The present results show thatMFA is relatively potent to antagonize physiologicbronchoconstrictors and have synergistic action withIso and Ami in bronchodilation. It is also suggestedthat MFA may have non-selective calcium antagonis-tic action and resemble Tri more closely than Ver orAmi in the mechanism of action.