虎杖苷对ADMA作用的正常兔主动脉血管条内皮功能的影响

目的 研究虎杖苷(PD)与非对称性二甲基精氨酸(ADMA)对正常兔主动脉血管条内皮功能的影响及PD与ADMA之间的相互作用。方法 通过绘制主动脉条在ADMA与PD分别作用和共同作用时对苯肾上腺素(PE)的收缩量一效曲线，计算并比较Emax和Kd值。结果正常主动脉条对ADMA无反应，PD或ADMA预处理后亦不影响其对PE的收缩反应。但PD使受ADMA预处理的主动脉条对PE的收缩反应呈剂量依赖性减弱,并引起Kd值增大、Emax减小。结论 ADMA或PD单独作用并不影响正常主动脉条的收缩功能及PE对α-受体的亲和力和Emax；但在ADMA存在时,PD能非竞争性拮抗主动脉条对PE的收缩反应。

Effect of polydatin on endothelial function in aorta vascular strips of healthy rabbits treated with ADMA

Object To study the effect of polydatin(PD)and asymmetric dimethylarginine(ADMA)on the endothelial function in aorta vascular strips of healthy rabbits and the interaction between PD and ADMA.Methods Dose-response curves of phenylephrine(PE)on the aortic strips with or without ADMA and/or PD.Emax and Kd from PE were obtained and compared.Results Normal aortic strips could not respond to ADMA.Pretreatment with either PD or ADMA had no effect on the contractive response of aortic strips to PE.But PD could significantly weaken the contractive response of aortic strips pretreated with ADMA caused by PE in a dose-dependent manner,increase Kd and decrease E of PE.Conclusion Either ADMA or PD alone does not influence the normal aortic strip contractive functions,the PE affinity to α-receptor,and Emax But PD could noncompetitively antagonize the contractive reaction of aortic strips to PE in the presence of ADMA.