金鸡菊黄酮对高血压小鼠的血压和肾素-血管紧张素系统的影响

Effect of Coreopsis tinctoria on blood pressure and renin-angiotensin system in hypertensive mice

目的:观察金鸡菊提取物70%乙醇洗脱物对高血压小鼠血压、血浆血管紧张素Ⅰ(AngⅠ)、血浆血管紧张素Ⅱ(AngⅡ)和组织中AngⅡ浓度的影响。方法:采用高盐(8g/100ml NaCl溶液)冷激法,连续20 d,形成小鼠高血压模型;将实验小鼠分为正常组、模型组、卡托普利组(40 mg/kg)和金鸡菊提取物70%乙醇洗脱物(40、80、160 mg/kg)组。连续灌胃给药28 d后,采用颈动脉插管法测定小鼠血压并取血,放射免疫法测定血浆AngⅠ、AngⅡ、及肾组织中AngⅡ的含量。结果:模型组血浆AngⅠ和组织中AngⅡ含量均明显高于正常组,其血压和血浆AngⅡ含量显著高于正常组;与模型组相比,金鸡菊提取物70%乙醇洗脱物(80、160 mg/kg)组血浆AngⅠ含量明显升高,血浆AngⅡ含量极显著降低,组织中的AngⅡ含量显著降低。结论:金鸡菊提取物70%乙醇洗脱物可明显升高AngⅠ水平,减少AngⅡ生成,推测其降压机制主要是通过影响肾素-血管紧张素系统,发挥AngⅠ拮抗剂或血管紧张素转化酶抑制剂的作用。

To observe the effects of Coreopsis tinctoria extraction 70% ethanol elution on blood pressure, plasma angiotensin Ⅰ, plasma angiotensin Ⅱ and tissue angiotensin Ⅱ in hypertensive mice. Methods： Established hypertension model of mouse by giving high-salt watercontinuously by gastric irrigation（ig） and keeping them in low-temperature environment 4 hours a day for 20 day; Then gave drug continuous- ly by ig for 28 days, mesured blood pressure, collected blood and kidney, and determined the plasma concentrations of angiotensinⅠ （ Ang I ）, AngⅡ and tissue homogenate Ang Ⅱ by radioimmunoassay. Results： Blood pressure, plasma levels of Ang I and Ang Ⅱ in tissue ho- mogenate in model group were obviously higher than those of normal group （ all P 〈 0.05）, and concentrations of plasma Ang Ⅱ were signifi- candy higher than those of normal group （ P 〈0.01 ）. Coreopsis tinctoria extraction 70% ethanol elution （ 80,160 mg/kg） group increased Ang I obviously, reduced plasma AngⅡ markedly （P 〈 0.01 ）, lessened local Ang Ⅱin tissue homogenate remarkably compared with those of model group （P 〈 0. 001 ）. Conclusions： Coreopsis tinctoria extraction 70% ethanol elution may increase Ang I obviously, and reduce Ang Ⅱ markedly , so its possible mechanism in the reduction of blood pressure of hypertensive mice is due to its effect on renin- angiotensin system, and plays a role similar to that of AngⅠ antagonist or angiotensin converting enzyme inhibitor.