Fozard J R, Mobarok Ali A T
Eur J Pharmacol. 1978 May 1;49(1):25-30. doi: 10.1016/0014-2999(78)90218-2.
The indirect sympathomimetic effects of N,N-dimethyl-5-hydroxytryptamine (bufotenine) have been analysed on the rabbit heart perfused in vitro by the Langendorff technique. Comparisons have been made with the effects of 5-hydroxytryptamine (5-HT), which activates tryptamine receptors, and dimethylphenylpiperazinium (DMPP), which stimulates nicotine receptors. Bufotenine, 5-HT and DMPP stimulated the rate and force of cardiac contraction but whereas all were powerful stimulants of cardiac rate, bufotenine and DMPP were much stronger stimulants of atrial and particularly ventricular tension than 5-HT. Responses to 5-HT were markedly reduced by perfusion of hearts with an excess of 5-HT, and those to DMPP, during perfusion with hexamethonium. A combination of 5-HT with hexamethonium was necessary to abolish the effects of bufotenine. The data suggest a dual mechanism of stimulant action of bufotenine on the cardiac sympathetic nerves of the rabbit heart involving activation of receptors sensitive to 5-HT and nicotine receptors.
已采用Langendorff技术在体外对兔心脏进行灌注，分析了N,N-二甲基-5-羟色胺（蟾蜍色胺）的间接拟交感神经效应。将其效应与激活色胺受体的5-羟色胺（5-HT）以及刺激烟碱受体的二甲基苯基哌嗪鎓（DMPP）的效应进行了比较。蟾蜍色胺、5-HT和DMPP均刺激心脏收缩的速率和力量，但尽管它们都是心率的强效刺激剂，但蟾蜍色胺和DMPP对心房尤其是心室张力的刺激作用比5-HT强得多。用过量的5-HT灌注心脏可使对5-HT的反应明显减弱，而在用六甲铵灌注期间，对DMPP的反应也会减弱。必须将5-HT与六甲铵联合使用才能消除蟾蜍色胺的效应。数据表明，蟾蜍色胺对兔心脏交感神经的刺激作用存在双重机制，涉及激活对5-HT敏感的受体和烟碱受体。
