内皮素 - 1对离体动脉的收缩作用及舒张药物的对抗效应

摘要

Objective　To observe the characteristics of vasoconstriction caused by endothelin - 1 and determine the antagonistic effect of vasodilators. Methods　Vasomotory test of the isolated rat common carotid artery was done to compare the influence of endothelin - 1 (ET - 1) and noradrenaline (NE)on artery tension in vitro, and detect the antagonistic effects of vasodilators on ET - 1 induced vasoconstriction. Results　Endothelin - 1 resulted in a constant constriction which was concentration - dependent in isolated rat common carotid arteries. The median effective concentration (EC50) of endothelin - 1 and noradrenaline were 1.8 × 10-9mol/L and 3.4 × 10-8mol/L respectively. The EC50 of noradrenaline was 18.9 times of that of endothelin - 1. Lidocaine, nifedipine, papaverine, sodium nitroprusside, and anisodamine all relaxed endothelin - 1 - induced vasoconstriction. The strongest among those vasodilators was sodium nitroprusside, whereas lidocaine and anisodamine weaker. Conclusions　Endothelin - 1 induces potent and persistent vasoconstriction of isolated arteries. Vasodilators can reduce endothelin - 1 - induced vasoconstriction.%目的　研究内皮素 - 1（Endothelin - 1，ET - 1）收缩血管的特性及显微血管外科常用舒张药物的对抗效应。方法　采用离体血管舒缩功能的实验技术比较ET - 1与去甲肾上腺素（noradrenaline，NE）对离体动脉张力的影响，同时检测舒张药物对ET - 1收缩血管的拮抗作用。结果　ET - 1使离体大鼠颈总动脉环产生浓度依赖性的恒定收缩，ET - 1与NE的半数有效浓度(median effective concentration,EC50)分别为1.8 × 10-9 mol/L和3.4 × 10-8 mol/L，NE的EC50值为ET - 1的18.9倍。血管舒张药如利多卡因、硝苯啶、罂粟硷、硝普钠、山莨菪硷，能有效对抗ET - 1的缩血管作用。其中以硝普钠最强，利多卡因与山莨菪硷较弱。结论　ET - 1对离体动脉具有强大而持久的收缩效应。血管舒张药可以减弱ET - 1的缩血管作用。