钩藤叶生物碱有效部位血管舒张活性的筛选
Relaxing effect of the crude extracts of leaves of Uncaria rhynchophylla (Miq.) Jacks on isolated vascular smooth muscle of rabbits
目的：研究钩藤叶生物碱有效部位（ULA）及其所含成分异去氢钩藤碱（ICN）、微量成分喜果苷（VIL）对离体兔血管平滑肌的作用及其机制。方法：以离体家兔胸主动脉环为实验标本，观察ULA、ICN和VIL对甲肾上腺素（NE）、氯化钾（KCl）引起的兔主动脉条收缩的影响；对氯化钙 (CaCl2) 累积收缩量效曲线的影响。结果：ULA（0.001~0.1 mgomL-1）和主要成分ICN（1×10 -6 ~1×10 -4 moloL-1）能显著抑制KCl诱导的主动脉环收缩，并呈现浓度依赖性，EC50值分别为0.02 mgomL-1和1.66×10-5 moloL-1，但对NE预收缩的主动脉环舒张作用较弱；微量成分VIL（3×10-5 ~ 3×10-4 moloL-1）不能抑制NE、KCl诱导的主动脉环收缩。结论：ULA和ICN具有舒张离体兔血管平滑肌的作用，其作用机制可能是通过阻滞血管平滑肌细胞膜上的电压依赖性钙通道，减少细胞外 Ca2+内流，从而引起血管舒张，与受体操纵性钙通道关系不大。VIL无舒张血管平滑肌的作用，但其是否具有降压作用有待进一步研究。
Objective To study the relaxing effect and its mechanism of the crude extracts of leaves of Uncaria rhynchophylla (Miq.) Jacks (ULA), isocorynoxeine (ICN) and vincoside-lactam (VIL) on isolated vascular smooth muscle of rabbits. Methods Preparations of isolated thoracic aorta of rabbits were prepared for study. The effect of ULA, ICN and VIL on the preparations pre-contracted with noradrenaline (NE) or KCl was investigated. The influence of them on the cumulative concentration-response curves of CaCl2 was studied. Results ULA (0.001~0.1 mgomL-1) and ICN (1×10-6~1×10-4 moloL-1) had concentration-dependent relaxing effects on isolated aorta strips of rabbits pre-contracted with NE with EC50 of 0.02 mgomL-1 and 1.66×10-5 moloL-1, respectively. However, the two agents had weak relaxing effects on the preparation pre-contracted with KCl. Moreover, VIL had no relaxing effect on the preparations pre-contracted with NE or KCl. Conclusions ULA and ICN can relax isolated vascular smooth muscle of rabbits; the mechanism is associated with the inhibition of Ca2+ channels.
张琳、袁丹、齐文、杨丽娟
基础医学药学生理学
钩藤叶异去氢钩藤碱喜果苷家兔主动脉条钙通道钾通道
leaves of Uncaria rhynchophylla (Miq.) Jacksisocorynoxeinevincoside-lactamrabbitaortic stripsCa2+ channelsK+ channels
张琳,袁丹,齐文,杨丽娟.钩藤叶生物碱有效部位血管舒张活性的筛选[EB/OL].(2015-01-04)[2025-08-05].http://www.paper.edu.cn/releasepaper/content/201501-20.点此复制
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