【摘要】 采用恒流灌注在体大鼠肾动脉的实验方法。结果表明,组胺可引起肾血管剂量依赖性扩张。单独或联合应用组胺H₁、H₂ 受体拮抗剂苯海拉明和甲氰咪胍,均可使组胺的量效曲线平行右移。无论是否同时应用苯海拉明,甲氰咪胍使组胺量效曲线右移的剂量比是相近的。经双倒数作图证明,茉海拉明和/或甲氰咪胍对组胺扩张肾血管的作用是一种竞争性拮抗。实验证明,在大鼠肾血管中,存在H₁和H₂两类受体。H₂ 受体的扩血管作用不被H₁受体的扩血管作用所掩盖。更多还原

【Abstract】 The effect of histamine on renal vasculature has been investigated by constant flow perfusion technique in the rat. Results indicate that histamine induces dose-dependent renal vasodilation. In the presence of diphenhydramine and/or cimetidine the dose-response curve of histamine shifts to the right parallelly. No matter whether diphenhyardmine is present or not, cimetidine can shift the dose-response curve to the right in the same extent. The pA 2 value for diphenhydramine-hista-mine as calculated was 7.5 which approximats the value obtained from other tissues. While the pA2 value for cimetidine-histamine was 7.3 which is higher than the value obtained from other tissues. According to the double-reciprocal plot, it is suggested that diphenhydramine and/or cimetidine antagonize renal vasodilation induced by histamine competitively in the rat. Both histamine H1 and H2 receptors mediating vasodilation effect are present in the rat renal vasculature. The effect mediated by H2 receptor is not masked by the effect mediated by H1 receptor.更多还原