Levi R, Ganellin C R, Allan G, Willens H J
Eur J Pharmacol. 1975 Nov;34(1):237-40. doi: 10.1016/0014-2999(75)90246-0.
To further characterize the receptor mediating histamine-induced impairment of atrioventricular conduction, the effects of two selective histamine H1-receptor agonists, 2-(2-pyridyl)-ethylamine (PEA) and 2-(2-thiazolyl)-ethylamine (ThEA), were investigated using the isolated guinea pig heart. These effects were compared with those of histamine and other selective agonists. PEA and ThEA produced a weak stimulation of cardiac rate and contractility; however, they produced a marked prolongation of atrioventricular conduction. The orders of relative potencies observed substantiate the hypothesis that H2-receptors mediate the positive inotropic and chronotropic effects and H1-receptors mediate the negative dromotropic effect of histamine.
为了进一步明确介导组胺引起的房室传导障碍的受体，我们使用离体豚鼠心脏研究了两种选择性组胺H1受体激动剂2-(2-吡啶基)-乙胺（PEA）和2-(2-噻唑基)-乙胺（ThEA）的作用。将这些作用与组胺和其他选择性激动剂的作用进行了比较。PEA和ThEA对心率和收缩力有微弱的刺激作用；然而，它们使房室传导明显延长。观察到的相对效价顺序证实了以下假说：H2受体介导正性肌力和变时作用，而H1受体介导组胺的负性变传导作用。
