钩藤中不同成分降压作用的差异

目的：比较钩藤中提取的异钩藤碱、钩藤碱、钩藤总碱及非生物碱部分的降压作用。方法：大鼠麻醉后经颈总动脉插管记录外周血压和经股静脉微量输注实验用药。结果：实验表明钩藤中４种成分的降压强度为异钩藤碱（４２．０％）〉钩藤碱（３２．１％）〉钩藤总碱（２１．３％）〉钩藤非生物碱（１２．４％）。结论：提示钩藤中主要降压成分为异钩藤碱的钩藤碱。

Different Hypotentive Effects of Various Active Constituents Isolated from Uncaria rhynchophylla

Hypotensive effects of rhynchophylline, isorhynchophylline, total alkaloid and non alkaloid fraction isolated from Uncaria rhynchophylla (Miq ) Jacks. were compared Change in peripheral blood pressure was recorded by inserting a catheter into the right common carotid artery of anaethetized rat, while each of the four hypotensive constituents was injected individually into the femoral vein by a microinfusion pump Results of the findings showed that the four constituents in U rhynchophylla displayed different hypotensive potency in the order of isorhynchophylline lowering of mean arterial pressure (MAP) by 42 0%] > rhynchophylline (lowering of MAP by 32 1%) > total alkaloid (lowering of MAP by 21 3%) > non alkaloid fraction (lowering of MAP by 12 4%) It was concluded that isorhynchophylline and rhynchophylline were the main hypotensive constituents in U rhynchophylla