Frković A, Skrobonja A, Atanacković D
Toxicological Laboratory of the Health Center, Rijeka.
Acta Physiol Pharmacol Bulg. 1988;14(4):43-8.
The effect of histamine, prometasin (the blocker of histamine H-1 receptor) and cimetidin (the blocker of histamine H-2 receptor) on the frequency of the isolated right atrium of rat was studied. Histamine, prometasin and cimentidin were applied cumulatively in concentrations of 5.4 X 10(-6) to 16.3 X 10(-3) mmol/l so that each new concentration was 3.3 times higher than the preceding one. The positive chronotropic effect of histamine was shown to be strongest with a concentration of 5.4 X 10(-3) mmol/l. Prometasin and cimentidine applied in increasing concentrations gave a negative chronotropic effect. Prometasin and cimetidin applied in a concentration of 5.4 X 10(-3) mmol/l before histamine, decreased the positive chronotropic effect of histamine to more than 60% no matter whether prometasin and cimetidin were applied alone or together. This finding suggests that the effect of histamine on rat heart is mainly realized via histamine H-1 and H-2 receptors and partly through releasing catecholamines from the adrenergic nerve terminal.
研究了组胺、溴苯那敏（组胺H-1受体阻滞剂）和西咪替丁（组胺H-2受体阻滞剂）对大鼠离体右心房频率的影响。组胺、溴苯那敏和西咪替丁以5.4×10⁻⁶至16.3×10⁻³mmol/L的浓度累积给药，使得每个新浓度比前一个浓度高3.3倍。结果显示，组胺浓度为5.4×10⁻³mmol/L时正性变时作用最强。随着溴苯那敏和西咪替丁浓度增加，它们呈现负性变时作用。在组胺给药前，以5.4×10⁻³mmol/L的浓度应用溴苯那敏和西咪替丁，无论它们单独应用还是联合应用，都能使组胺的正性变时作用降低至60%以上。这一发现表明，组胺对大鼠心脏的作用主要通过组胺H-1和H-2受体实现，部分通过从肾上腺素能神经末梢释放儿茶酚胺来实现。
