U50,488H对大鼠腹主动脉的舒张作用及其机制

目的 观察Ｕ５０,４８８Ｈ（选择性k-阿片受体激动剂）对大鼠腹主动脉的舒张作用。并探讨其机制。方法 采用离体血管灌流实验,测定血管张力的改变。结果 （１）Ｕ５０,４８８Ｈ对大鼠腹主动脉具有明显的舒张作用;（２）Ｕ５０,４８８Ｈ对大鼠腹主动脉的舒效应依赖于内皮细胞的存在;（３）优降糖可明显抑制Ｕ５０,４８８Ｈ对大鼠腹主动脉的舒张作用;（４）Ｕ５０,４８８Ｈ的舒张血管疚２与Ｍ受体、β３受体、前列腺素及ＮＯ无关。结论 Ｕ５０,４８８Ｈ是一种有效的扩血管物质,其舒张血管的效应具有内皮依赖性,且与Ｋ^ ATP通道有密切关系。

Relaxant effect of U50,488H on abdominal aorta in rats and its mechanism

AIM　To investigate the relaxant effect of U50,488H (a selectiveκ-opioid receptor agonist) on abdominal aorta and its underlying mechanism in the rat.METHODS　Isolated abdominal aorta was perfused and the tension of the vessel was measured.RESULTS　①U50,488H had the significant dose-dependent relaxant effect on rat abdominal aorta; ②The relaxant effect of U50,488H on rat abdominal aorta was endothelium-dependent; ③The relaxant effect of U50,488H on rat abdominal aorta was inhibited in presence of glybenclamide; ④The relaxant effect of U50,488H on blood vessel bore no relationship to M-receptor, β-receptor, prostaglandin and nitric oxide (NO).CONCLUSION　U50,488H is a powerful endothelium-dependent vasodilator, related to K+　ATP channels.