黄芪皂苷甲抑制压力过载型心肌肥厚大鼠肾素-血管紧张素的过度激活

Inhibitory effect on activated renin-angiotensin system by astragaloside Ⅳ in rats with pressure-overload induced cardiac hypertrophy

目的:探讨黄芪皂苷甲(AsⅣ)对压力过载型左心室肥厚大鼠肾素-血管紧张素系统过度激活的影响。方法:采用缩窄大鼠腹主动脉制备压力过载所致的左心室肥厚模型。造模12周后分别给予灌服黄芪皂苷甲(1.0,3.3 mg.kg-1)12周。给药结束后,应用形态测量学测定左室质量指数;采用ELISA法测定大鼠血浆血管紧张素Ⅱ(AngⅡ)、醛固酮(A ld)含量和心肌组织AngⅡ含量;采用Real tim e PCR测定心肌组织ACE,AT1和AT2mRNA含量;采用W estern b lot法测定心肌组织AT1和AT2的蛋白表达。结果:与模型组相比,黄芪皂苷甲能降低左室质量指数;生化测定结果表明,模型组血浆AngⅡ和A ld含量较假手术组明显增加,心肌组织的AngⅡ含量也较假手术组显著提高。黄芪皂苷甲能降低模型组血浆AngⅡ和A ld含量以及心肌组织的AngⅡ含量;黄芪皂苷甲具有下调模型动物心肌组织血管紧张素转化酶(ACE)的基因表达,上调模型动物心肌组织AT2的基因和蛋白表达,但对模型动物心肌组织中上调的AT1基因和蛋白表达无逆转作用。结论:黄芪皂苷甲能够抑制压力过载型心肌肥厚大鼠肾素-血管紧张素系统的过度激活,这可能是其逆转左室肥厚的途径之一。

Objective: To investigate the effect of astragaloside Ⅳ(As Ⅳ) on the activation of rennin-angiotensin system in rats with pressure-overload induced cardiac hypertrophy.Method: Left ventricle hypertrophy was induced by abdominal aorta banding between bilateral renal aortas for 12 weeks.Rats were given astragaloside Ⅳ 1.0 mg·kg-1 and 3.3 mg·kg-1 for 12 weeks,respectively.After treatment,the left ventricular mass index(LVMI)was calculated by morphometry methods.Plasma and cardiac tissue angiotensin Ⅱ,and plasm...