葛根素对大鼠腹主动脉的舒张作用及其机制

Vasodilation effect of puerarin on abdominal aortic artery in the rat and the underlying mechanism

目的 :研究葛根素 (Puerarin ,Pue)对大鼠腹主动脉离体血管的舒张作用特点并探讨其机制 .方法 :雌性SD大鼠1 6只 ,常规方法制备离体血管环标本 ,随机分为Pue浓度依赖组、Pue时间依赖组、内皮依赖组、L NAME组、优降糖组、L NAME与优降糖共同作用组、阿托品组、普耐络尔组、消炎痛组 .用离体血管灌流法灌流大鼠腹主动脉环 ,血管环基础张力定为 9.8× 1 0 -3 N(1g) ,各组分别加入不同酶抑制剂或通道阻滞剂 ,孵育后加入 1 0 -2 mol·L-1 Pue ,测定血管环张力变化 .结果 :Pue在 1 0 -8～ 1 0 -2 mol·L-1 范围内对腹主动脉具有剂量依赖性的舒血管效应 ,以单浓度 (5× 1 0 -3 mol·L-1 ,EC50 浓度 )Pue作用于大鼠腹主动脉后 ,1 8min达到最大舒张效应 (4 8.0± 6 .5 ) % ;Pue的舒张血管效应在血管去内皮后可降低 (6 8.0± 6 .5 ) % ;在L NAME实验组和优降糖实验组中分别降低(5 8.0± 3.8) %和 (4 8.0± 5 .4 ) % ,与对照组相比两组均存在显著差异 (P <0 .0 5 ) ;在L NAME与优降糖共同作用组以及阿托品组 ,普耐络尔组 ,消炎痛组中 ,血管舒张的受抑制程度与对照组差别无显著性 (P >0 .0 5 ) .结论 :Pue具有内皮依赖性的舒血管效应 ,该作用与NO系统和ATP 敏感的钾通道有关 .

AIM: To investigate the relaxative characteristics of puerarin on abdominal aortic artery in the rat and its mechanism. METHODS: The aortic rings were prepared from 16 female SD rats with the routine method, and then separated into 9 groups randomly . We perfused the aortic rings, gave the resting tension of 1g, and added the different pharmacological agents (enzyme inhibitors or receptor antagonists). The change in tension was detected on a computer via amplifier. RESULTS: Puerarin at 10 -8 -10 -2 mol·L -1 relaxed rat aorta in a dose dependent manner. The relaxative effect of puerarin reached the highest level [(48.0±6.5) %] in the presence of the single concentration of puerarin (5×10 -3 mol·L -1 ,EC 50 ) at min 18, and the effect was significantly attenuated by (58.0±3.8)% in the L NAME group, (48.0±5.4)% in glybenclamide group and (68.0±6.5)% in the endothelium group, higher than that of the control group ( P <0.05). But that was not changed in the group of atropin, propranolol and indomethacin ( P >0.05). CONCLUSION: These results indicate that puerarin relaxes the aortic artery in an endothelium dependent manner, and the vasodilation of puerarin is via NO system and KATP channel.