Sako J, Yasuda Y
Department of Surgery, Ohmiya Medical Center, Jichi Medical School.
Nihon Shokakibyo Gakkai Zasshi. 1993 May;90(5):1405-15.
We investigated the effect of cimetidine and histamine on splanchnic circulation in the dogs. Hepatic artery, superior mesenteric artery and portal vein were cannulated to measure each blood pressure. Each blood flow was evaluated utilizing electromagnetic blood flowmetry. And vascular resistances were calculated by measured blood pressure and blood flow. Cimetidine, histamine, 2-PEA (H1-agonist), dimaprit (H2-agonist) and mepyramine maleate (H1-antagonist) were given by intravenous bolus to the dogs. Histamine caused vasodilation of hepatic artery but vasoconstriction of superior mesenteric artery and these effects were similar to the effect of 2-PEA. These hemodynamic responses to histamine were inhibited by H1-antagonist but not inhibited by H2-antagonist. Cimetidine produced dilatation of hepatic artery but constriction of portal vein, superior mesenteric artery and reduced total hepatic blood flow. These effects were not inhibited by H1-antagonist. We concluded that cimetidine did not stimulated H1, H2-receptors rather than had the own effects and that H1-receptor was superior to H2-receptor on splanchnic circulation in the dogs.
我们研究了西咪替丁和组胺对犬内脏循环的影响。分别将导管插入肝动脉、肠系膜上动脉和门静脉以测量各血管血压。利用电磁血流仪评估各血管血流量。并根据测得的血压和血流量计算血管阻力。通过静脉推注的方式给犬注射西咪替丁、组胺、2-苯乙胺（H1激动剂）、二甲双胍（H2激动剂）和马来酸氯苯那敏（H1拮抗剂）。组胺可使肝动脉血管舒张，但使肠系膜上动脉血管收缩，这些效应与2-苯乙胺的效应相似。组胺引起的这些血流动力学反应被H1拮抗剂抑制，但未被H2拮抗剂抑制。西咪替丁可使肝动脉扩张，但使门静脉、肠系膜上动脉收缩，并使肝脏总血流量减少。这些效应未被H1拮抗剂抑制。我们得出结论，西咪替丁并非通过刺激H1、H2受体发挥作用，而是具有自身效应，且在犬内脏循环中，H1受体比H2受体更具优势。
