槲皮素对原发性高血压患者肠系膜动脉平滑肌细胞钙激活钾通道活性的影响  

Effect of Quercetin on Calcium-Activated Potassium Channels in Mesenteric Artery Smooth Muscle Cells in Essential Hypertensive Patients

作　　者：陈辉[1] 赵文强[1] 刘应才[2] 刘慧芳[2] 潘金生[2] 曾晓荣[3] 

机构地区：[1]江苏大学第四附属医院心内科,江苏镇江212000 [2]泸州医学院附属医院心内科,四川泸州646000 [3]泸州医学院心肌电生理研究所,四川泸州646000

出　　处：《中华高血压杂志》2008年第8期707-711,共5页Chinese Journal of Hypertension

基　　金：四川省教育厅自然科学科研基金重点项目(2004A057)

摘　　要：背景槲皮素是是一种自然界广泛分布的具有多种生物活性的黄酮类化合物。大量研究已证实槲皮素能够通过多种方式实现降血压效应。但是对于槲皮素通过离子通道降血压的机制目前还不十分清楚。目的观察槲皮素对高血压患者肠系膜动脉平滑肌细胞钙激活钾通道(K_(Ca))活性的影响,以探讨槲皮素通过离子通道降血压的机制。方法选取需择期行腹部手术者,共26例,分为两组,血压正常组14例,原发性高血压(EH)组12例。取肠系膜动脉小分支,用急性酶消化法获得单个肠系膜动脉平滑肌细胞。然后应用单通道细胞膜片钳技术观察不同浓度槲皮素对肠系膜动脉平滑肌细胞钙激活钾通道开放概率(P_o)、电流幅度值(A_m)、平均开放时间(T_o)、平均关闭时间(T_c)等各指标的影响。结果在 inside-out patch 方式下,随着浴液中槲皮素浓度依赖性地增高正常血压者和高血压患者肠系膜动脉平滑肌细胞 K_(Ca)通道 P_o,通道 A_m及通道 T_o 变化不大,而通道 T_c 均明显缩短。各槲皮素浓度下的两组 K_(Ca)通道 P_o 增长率(⊿P_o%)差异无统计学意义。结论槲皮素能直接激活人类血管平滑肌细胞 K_(Ca)通道。高血压患者和正常血压者血管平滑肌细胞 K_(Ca)对槲皮素的反应性无明显区别。槲皮素激活钙激活钾通道可能是其降血压的一种机制。Background Quercertin, a kind of flavonoids, widely distributes in nature with various biological and pharmacological effects. Quercertin was found having the effect of decreases in blood pressure via various pathways. However, its effect on ion channels in cells are unclear. Objective To explore the mechanism by which quercetin decreases blood pressure, investigate the effect of quercetin on calcium-activated potassium channels （KCa） in mesenterie artery smooth muscle cells（MASMC） obtained during abdominal＇operation in patients with essential hypertension. Methods Mesenteric artery branches were excised from patients including normotensives （n=14） and hypertensives（n= 12） who were carried out abdominal operations. Single mesenteric artery smooth muscle cell（SMC） was obtained by enzymization. Using the single channel current recording technique, single channel open probability（Po ）, current amplitude （ Am ）, mean open time （ To ） and mean close time （Tc） of MASM Kca were studied with different concentrations of quercertin solution. Results In inside-out patch test, quercertin enhanced Kca Po of MASMC in both normotensives and hypertensive patients in a dose dependent manner with significantly shortened Tc and little change in Am or To. No difference in the growth rate of Po （ △ Po %） was found in the presence of various different quercertin concentrations between normotensives and hypertensive patients. Conclusion Quercertin activated Kca channels of human vascular smooth muscle cells. No difference in the reactivity of the vascular smooth muscle cells Kca by quercertin between the essential hypertension and the normotensive was shown. Activated Kca channels by quercertin may be one of the mechanisms by which quercertin decreases blood pressure.

关 键 词：槲皮素 原发性高血压 钙激活钾通道 膜片钳技术 

分 类 号：R544.1[医药卫生—心血管疾病] R543.5[医药卫生—内科学]