山莨菪碱对正常及自发性高血压大鼠离体血管舒张功能的影响

Influence of anisodamine on in vitro vascular relaxation function in normal and spontaneous hypertension rats

目的：观察山莨菪碱对离体正常（Wistar）大鼠及自发性高血压大鼠（spontaneously hypertensive rats,SHR）腹主动脉舒张作用的影响,并探讨其可能的作用机制。方法：采用大鼠离体腹主动脉环（长度为4-5mm的血管）灌流技术,观察山莨菪碱对正常大鼠及SHR血管舒张功能的影响,并观察苯肾上腺素（phenylephrine,PE）、左旋硝基精氨酸甲酯（L-NAME）预处理对山莨菪碱作用的影响。结果：山莨菪碱对PE预收缩的正常大鼠内皮完整和去内皮血管的舒张作用差异显著（P〈0.05）;对PE预收缩的SHR内皮完整及去内皮血管环,山莨菪碱均具有显著舒张作用,呈剂量-效应关系,最大舒张率分别为（78.6±6.9）%和（65.76±11.39）%,无统计学差异。用NOS抑制剂L-NAME预处理正常大鼠内皮完整的血管环,可显著地抑制山莨菪碱诱导的舒张作用（P〈0.05）。山莨菪碱对SHR血管的舒张作用能够被L-NAME抑制,抑制前后最大舒张率分别为61%和11.9%（P〈0.01）。结论：山莨菪碱可能通过内皮和平滑肌2条途径发挥舒张大鼠离体腹主动脉的作用。

Objective：To observe the influence of anisodamine on relaxation function of isolated Wistar and spontaneously hypertensive rat（SHR）aortic rings,and to investigate the underlying mechanism.Methods：The SHR aorta rings were irrigated with anisodamine and the effect of anisodamine on relaxation of isolated aortic rings was observed in normal and spontaneous hypertension rats before and after pretreatment with phenylephrine（PE）or L-nitroarginine methylester（L-NAME）.Results：The accumulated concentration of anisodamine showed significantly different relaxing effects on PE-precontracted aortic ring with or without endothelium（P〈0.05）in normal rats.Anisodamine showed obvious relaxing effect on PE-precontracted aortic ring with and without endothelium,and the relaxing effect was in a dose-dependent manner,with the maximal relaxation being（78.6±6.9）% and（65.76±11.39）%,respectively（P〉0.05）.Pretreatment with non-selective NOS inhibitor L-NAME significantly inhibited the relaxing effect of anisodamine on the aortic ring with endothelium（P〈0.05）.L-NAME partially blocked the relaxing effect of anisodamine on SHR rats,with the maximal relaxation being 61% and 11.9%（P〈0.01）before and after blocking,respectively.Conclusion：Anisodamine can enlarge isolated aorta of rats through endothelial and smooth muscle.