中西医结合对自发性高血压大鼠心肌血管紧张素Ⅱ 1型受体mRAN和蛋白表达的影响

目的观察降压胶囊联合尼莫地平对自发性高血压大鼠(SHR)的降压作用,并探讨其对大鼠心肌组织血管紧张素Ⅱ(AngⅡ)1型受体蛋白和mRAN基因表达的影响。方法将66只SHR大鼠随机分为6组,即模型组、降压胶囊大剂量联合尼莫地平组(联合大剂量组)、降压胶囊小剂量联合尼莫地平组(联合小剂量组)、降压胶囊大剂量组(中药大剂量组)、降压胶囊小剂量组(中药小剂量组)、尼莫地平组。连续灌胃8周,每日1次,正常饲料喂食。8周末,动物麻醉取血和分离心脏组织,放射免疫法测定AngⅡ含量,逆转录-多聚酶链式反应(RT-PCR)法测定各组大鼠心肌mRNA的含量,采用Western免疫印迹(Western Blot)法测定各组大鼠心肌AT1R受体的蛋白表达。结果与模型组比较,联合大、小剂量组,中药大、小剂量组和尼莫地平组SHR大鼠血压、血浆AngⅡ含量均显著下降(P0.05或P0.01)。与模型组比较,联合大、小剂量组,中药大剂量组和尼莫地平组对大鼠心肌AT1受体蛋白表达和mRNA基因表达均显著降低(P0.05或P0.01);且联合大、小剂量组对AT1受体蛋白表达及联合大剂量组mRNA基因表达较尼莫地平组显著降低(P0.05或P0.01)。结论降压胶囊联合尼莫地平可抑制血中AngⅡ水平,降低大鼠血压,其治疗机理与抑制心肌AngⅡAT1受体mR-NA含量的增加和降低其蛋白的表达有关,其降低水平和治疗作用优于单纯用中药和单纯用西药。

Effects of Integration of Chinese and Western Medicine on mRNA and Protein Expression of Myocardial Angiotension II Type 1 Receptor in the Rats with Spontaneously Hypertension

Objective：To observe the effects of jiangya capsule combined with nimodipine on anti-hypertension in the rats with spontaneous hypertension and explore the impacts on protein and mRNA expression of myocardial angiotensin Ⅱ（Ang Ⅱ）type 1（AT1）receptor.Methods：66 rats with spontaneous hypertension were randomly divided into 6 groups,named model group,high-dose of jiangya capsule combined with nimodipine group（high dose of combination group）,low-dose of jiangya capsule combined with nimodipine group（low dose of combination group）,high-dose of jiangya capsule group（high dose of Chinese herbal medicine group）,low-dose of jiangya capsule group（low dose of Chinese herbal medicine group）and nimodipine group.Gastric infusion was administered continuously for 8 weeks,once per day and the forage feeding was applied normally.At the end of the 8th week,after anesthetized,blood was collected and the heart tissues were separated.Radioimmunoassay was used to determine Ang Ⅱ level,RT-PCR was to the content of mRNA and Western Blot was to the protein expression of myocardial AT1 receptor in the rats of each group.Results：Blood pressure and plasma Ang Ⅱ content decreased significantly in high-dose and low-dose combination groups,high-dose and low-dose groups of Chinese herbal medicine,as well as nimodipine group as compared with model group（P0.05 or P0.01）.The mRNA and protein expression of AT1 receptor decreased significantly in high-dose and low-dose combination groups,high-dose group of Chinese herbal medicine,as well as nimodipine group as compared with model group（P0.05 or P0.01）.The protein expression of AT1 receptor in high-dose and low-dose combination groups,as well as mRNA expression in high-dose combination group were all reduced significantly as compared with nimodipine group（P0.05 or P0.01）.Conclusions：Jiangya capsule combined with nimodipine inhibits Ang Ⅱ level in blood and reduces rat blood pressure,which is relevant in mechanism with the suppression of mRNA and protein expression of myocardial Ang Ⅱ AT1 receptor;and the decrease extent as well as the therapeutic effect of the combined medication are superior to single administration of either jiangya capsule or nimodipine.