血灵侧脑室注射对大鼠动脉血压和心率的影响

Effects of Xueling with intracerebro ventricular on blood pressure and heart rate in rats

目的 :血灵是降血压中药制剂 ,本实验探讨血灵对心血管中枢的作用及其机理。方法 :将药物微量地注射入麻醉大鼠侧脑室 ,观察注药后 60min内血压和心率的变化。结果 :①侧脑室注射血灵 ( 1 0mg/2 0 μl)引起动脉血压明显升高 ,2 5min时达到峰值 ,增幅为 2 6.59% ;心率增加 ,增幅为 1 5.76%。侧脑室注射相同容积的NS ,血压和心率无明显影响。②血压升高与侧脑室注射血灵的剂量呈明显的剂量 -效应关系。③侧脑室注射血灵致血压和心率的增加效应可被侧脑室内预先注射 β受体阻断剂普萘洛尔 ( 2 0 μg/2 0 μl)或M受体阻断剂阿托品 ( 1 0 μg/2 0 μl)拮抗 ,但不能被α受体阻断剂酚妥拉明 ( 2 5μg/2 0 μl)拮抗。 结论 :血灵具有中枢性升高动脉血压和心率作用 ,该作用可能部分地由脑内的 β受体和M受体介导。进而推测血灵的降压效应是通过心血管系统的外周活动起作用的。

OBJECTIVE:Xueling is a preparation of traditional Chinese medicine that has hypotensive effect.The present experiment was undertaken to study the effects of Xueling on cardiovascular center and it′s mechanism.METHOD:Drugs were injected into anaesthetized SD rats lateral ventricle to observe the change of arterial blood pressure(BP) and heart rate(HR) within 60 min.RESULTS:①Injection of Xueling(10mg/20ug) into the rat lateral ventricle resulted in 26.59% increasement in BP which reached its peak at 25 min and 15.76% increasemant increase in HR.Injection of NS with the same volume into the lateral ventricle did not resulted in significant change of BP and HR.②The relationship of effect between the elevation in arterial blood pressure and dosage of xueling was obvious.③This effect of Xueling could be partially antagonized by the injection of propranolol(β receptor antagonist,20μg/20μl) or atropine(M receptor antagonist,10μg/20μl)into the lateral ventricle,but could not be antagonized by phentolamine(α receptor antagonist,25μg/20μl).CONCLUSION:Xueling can elevate BP and HR centrally,these effects are partly mediated by β and M receptor in brain.It could be inferred that hypotensive effect resulted by xueling is its peripheral action to cardiovascular system.