羟苯氨酮的舒张血管作用及其机理研究

STUDY ON VASORELAXATIONS OF OXYPHENAMONE AND ITS MECHANISM

目的 研究羟苯氨酮 (oxyphenamone ,Oxy)的舒血管作用及其作用机理。方法 离体兔血管制备生物测定法。结果 Oxy对离体兔肾动脉、股动脉和肠系膜动脉均有明显舒张作用且呈剂量依赖性 ;显著抑制去氧肾上腺素的缩血管作用 ;Oxy对 3 0mmol·L- 1 和 80mmol·L- 1 KCl缩血管作用均有显著抑制 ;对 80mmol·L- 1 KCl抑制作用的量效曲线与 3 0mmol·L- 1 KCl抑制作用的量效曲线比较 ,明显右移 ;对血管紧张素II的缩血管作用因浓度而异 ,低浓度加强而高浓度抑制。结论 Oxy对多种血管均有舒张作用 ,其机理可能与血管平滑肌细胞上的钙通道和钙激活的钾通道有关。

AIM To study the vasorelaxation action of oxyphenamone (Oxy) and its mechanism. METHODS The contractile response of isolated rabbit renal, femoral and mesentery artery preparations was determined. RESULTS Oxy was shown to inhibit the contractile force of renal, femoral and mesentery arteries induced by phenylephrine in a concentration dependent manner. The vasorelaxation produced by Oxy was not attenuated by removal of the endothelium. Oxy (10 -6 ～10 -4 mol·L -1 ) relaxed the contractions induced by KCl 30 mmol·L -1 as well as KCl 80 mmol·L -1 , but the contraction curve of KCl 80 mmol·L -1 was shifted significantly to the right. Oxy in lower concentration (10 -6 and 5×10 -6 mol·L -1 ) increased the contractions induced by Ang II, and in middle concentration (10 -5 mol·L -1 ) it did not affect the contractions induced by Ang II. Whereas in higher concentration (5×10 -5 mol·L -1 ) it obviously inhibited the contractions induced by Ang II. CONCLUSION Oxy showed significant vasorelaxation to various vascular preparations, and its vasorelaxation action is endothelium independent. The mechanism of its vasorelaxations seems to be related with Ca 2+ activated K + channel (K Ca channel) and Ca 2+ channel in vascular smooth muscle cells but its true mechanism needs further study.