Todorov S, Zamfirova R
Methods Find Exp Clin Pharmacol. 1985 Jul;7(7):357-60.
The effects of histamine and some agonists and antagonists of the two types of histaminergic receptors on adrenergic smooth muscle neurotransmission were studied. The experiments were carried out on electrical stimulated (0.1 Hz, 1 pulse, 1 msec pulse duration, supramaximal voltage) prostatic part of rat vasa deferentia. Histamine, 2-(aminoethyl) thiazole and 2-methylhistamine (H1-agonists) as well as dimaprit (H2-agonist) had a biphasic effect on smooth muscle contractions induced by electrical stimulation (ES): low drug concentrations potentiated and high concentrations markedly inhibited the ES-contractions. The agonist of H1-receptors pyridylethylamine in low concentrations did not affect the smooth muscle contractions and in high concentrations decreased their amplitude. Diphenhydramine and mepyramine (H1-antagonists) strongly potentiated (up to 250%) the ES-contractions, while the H2-antagonist cimetidine did not change them. These effects might be due to the interaction of the drugs tested with different populations of the histaminergic receptors.
研究了组胺以及两种组胺能受体的一些激动剂和拮抗剂对肾上腺素能平滑肌神经传递的影响。实验在大鼠输精管前列腺部进行电刺激（0.1Hz，1个脉冲，脉冲持续时间1毫秒，超最大电压）。组胺、2-（氨基乙基）噻唑和2-甲基组胺（H1激动剂）以及二甲双胍（H2激动剂）对电刺激（ES）诱导的平滑肌收缩有双相作用：低药物浓度增强，高浓度显著抑制ES收缩。低浓度的H1受体激动剂吡啶乙胺不影响平滑肌收缩，高浓度时降低其幅度。苯海拉明和美吡拉敏（H1拮抗剂）强烈增强（高达250%）ES收缩，而H2拮抗剂西咪替丁则无变化。这些效应可能是由于受试药物与不同群体的组胺能受体相互作用所致。
