钩藤碱抑制麻醉大鼠颈动脉窦压力感受性反射的研究  

Inhibitory effect of rhynchophylline on carotid sinus baroreflex in anesthetized rats

作　　者：刘宜先[1] 马慧娟[1] 高璐[1] 文之[1] 刘娜[1] 张翼[1] 何瑞荣[1] 

机构地区：[1]河北医科大学基础医学院生理教研室,河北050017

出　　处：《北京中医药大学学报》2009年第11期763-767,共5页Journal of Beijing University of Traditional Chinese Medicine

基　　金：河北省科技厅科技攻关资助项目(No.062761773);河北省教育厅资助项目(No.Z2006110)

摘　　要：目的研究钩藤碱(Rhy)对颈动脉窦压力感受性反射(CSB)的作用并探讨其作用机制。方法利用隔离灌流大鼠颈动脉窦技术,确定各项功能参数,如阈压(TP)、饱和压(SP)、平衡压(EP)、工作范围(OR)、最大斜率(PS)和平均动脉压反射性下降幅度(RD)等。Rhy(10、50、100μmol/L)溶于K-H液后灌流窦区,以斜坡方式升降窦内压来观察Rhy对CSB的影响。分别预先灌流一氧化氮合酶抑制剂L-NAME,钾通道阻断剂四乙铵(TEA)和￡-型钙通道开放剂Bay K8644后再给予Rhy,观察它们对Rhy作用的影响。结果Rhy浓度依赖性地抑制了CSB,使其各功能参数改变,TP和SP增大,PS和RD均减小。Rhy的抑制作用不能被L-NAME(300μmol/L)和TEA(1 mmol/L)预处理所取消,而可被Bay K8644(500 nmol/L)明显减弱。结论Rhy抑制了CSB,此作用可能是通过减弱压力感受器的牵张敏感性离子通道的钙内流来实现,而与NO和钾通道无关。Objective To study the effect of rhynchophylline（Rhy） on carotid sinus baroreflex（CSB） and the mechanism.Methods The technique of carotid sinus isolation and perfusion was used to determine the parameters of CSB,including threshold pressure（TP）,saturation pressure（SP）, equilibrium pressure（EP）,operating range（OR）,peak slope（PS） and reflex decrease（RD）.The influence of Rhy on CSB was observed in a slope manner after Rhy（10,50 and 100μmol/L） dissolving in K-H solution and then filling into carotid sinus.Nitric oxide synthase inhibitor[NG-nitro-arginine methyl ester（L-NAME）],potassium channel blocker[tetraethylammonium（TEA）]and agonist of L-type calcium channel（Bay K8644） were perfused into isolated carotid sinus before reperfusion of Rhy, and then the effects of them on Rhy were observed.Results Rhy inhibited CSB in a manner of dosedependent with the increase of TP and SP and the decrease of PS and RD.The inhibitory effect of Rhy was not affected by the pretreatment of L-NAME（300μmol/L） or TEA（1 mmol/L）,but attenuated by Bay K8644（500 nmol/L）.Conclusion Rhy inhibits CSB,which may be related to that Rhy attenuates calcium influx of mechanosensitive ion channel of baroreceptor but not related to NO channel or potassium channel.

关 键 词：钩藤碱 动脉压力感受性反射 一氧化氮合酶抑制剂 四乙胺 L-型钙通道开放剂 大鼠 

分 类 号：R285.5[医药卫生—中药学]