玄参对压力超负荷大鼠心室重构及心肌组织ET-1表达的影响

目的探讨玄参对压力超负荷大鼠心室重构、心肌组织内皮素-1(ET-1)的影响及其作用机制.方法腹主动脉不完全结扎法制备大鼠心室重构模型,同时设立假手术对照组.8周药物干预后,测量大鼠心率(HR)、收缩压(SBP)、舒张压(DBP)等指标;测定左心室及全心质量指数(LVWI、HWI);紫外分光光度法测定心肌SOD活性;放免法测定ET-1含量;RT-PCR测定心肌组织ET-1 mRNA基因表达水平.结果模型组大鼠HR、SBP、DBP、LVWI及HWI显著升高,而SOD活性则显著降低,ET-1浓度及ET-1 mRNA表达增加.玄参水提液能降低心率、血压、心脏质量指数,提升SOD活性,降低ET-1浓度及其基因表达水平.结论压力超负荷导致心室重构、氧化应激,心肌ET-1表达增强.玄参水提液可抑制心室重构,其机制可能与其抗氧化应激、下调ET-1表达有关.

The Study of Xuanshen on Ventricular Remodeling and Cardiac Endothelin-1 Expression in Rats Treated with Pressure-overload

OBJECTIVE: To investigate the influence of Xuanshen on cardiac endothelin-1 expression, ventricular remodeling and its mechanism in rats treated with pressure-overload. METHODS: The ventricular remodeling model was induced by abdominal aortic stenosis in rats. Meanwhile, sham-operated rats were established as the control group. 8 weeks after drug interference, heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), left ventricular weight and heart weight index (LVWI and HWI), the activity of superoxide dismutase (SOD), cardiac endothelin-1 concentration and its gene expression were determined. RESULTS: Compared with those of sham-operated rats, the HR, SBP, DBP, LVWI and HWI of the model rats were increased significantly. The activity of SOD decreased, the concentration of cardiac endothelin-1 and its gene expression increased. In groups treated with Xuanshen, the HR, SBP, DBP, LVWI and HWI declined and the activity of SOD was improved. Moreover, the concentration of cardiac endothelin-1 and its gene expression decreased. CONCLUSION: Pressure-overload may induce oxidative stress and over-expression of cardiac endothelin-1. Xuanshen can inhibit ventricular remodeling. The mechanism may be related to the inhibition of oxidative stress and down regulation of endothelin-1 expression.