莫索尼定与可乐定对自发性高血压大鼠作用的比较

目的: 比较莫索尼定与可乐定对自发性高血压大鼠(SHR) 的作用特点。方法: 采用颈动脉直接插管测压和尾动脉间接测压法, 一次或连续口服给药, 分别测定清醒和麻醉SHR 的血压及其心率变化。结果: 清醒SHR 一次大剂量口服莫索尼定降压与心率减慢作用呈剂量依赖性, 其10 倍剂量与可乐定作用相近;连续小剂量口服莫索尼定降压百分率与可乐定相仿, 心率减慢弱而短暂;在麻醉SHR, 小剂量口服莫索尼定降压作用与剂量相关;等剂量莫索尼定与可乐定降压百分率无显著差异(P>0.05) 。结论: 大剂量一次口服给药, 莫索尼定10 倍可乐定剂量对SHR 的作用与之相当, 小剂量连续口服给药, 莫索尼定和可乐定等剂量对SHR 的降压作用相当。

Comparison of effects of moxonidion and clonidine on decreasing blood pressure in spontaneous hypertensive rats

AIM: To compare the peculiarity of effects between moxonidine and clonidine on decreasing blood pressure in spontaneous hypertensive rats (SHR). METHODS: Arterial blood pressure and heat rate were directly determined by a catheter on the carotid artery or indirectly determined by a tail-cuff method in conscious and anesthetized SHR after once or repeatedly oral administration, respectively.RESULTS: Moxonidine showed a dose-dependent effect on reducing blood pressure and heat rate after once large dose oral administration in conscious SHR.The effect on decreasing blood pressure and heart rate after oral administration of 10 mg·kg^-1moxonidine was equal to the effects after oral administration of 1 mg·kg^-1clonidine.The rate of reducing blood pressure by moxonidine was equal to that by clonidine, and the decreasing in heart rate was little and short after repeatedly small dose oral administration of moxonidine.Moxonidine exerted a dose-dependent effect on reducing blood pressure after small dose oral administration in anesthetized SHR.There was no significant difference between moxonidine and clonidine in reducing rate of blood pressure after same dose administration (P>0.05).CONCLUSION: The effects of 10mg·kg^-1moxonidine on reduced blood pressure and heart rate in SHR is equal to the effects of 1mg·kg^-1clonidine after once large dose oral administration.There is no significant difference between the moxonidine and clonidine of the same dose in reducing blood pressure after repeatedly small dose oral administration in SHR.