依普利酮对醛固酮输注大鼠肾脏肾素受体表达的影响

目的：探讨依普利酮（Epl）对醛固酮（ALD）输注大鼠肾脏肾素受体表达的影响。方法：18只SD大鼠随机分为3组：对照组、ALD输注组、Epl治疗组，均皮下埋置渗透性微泵，其中ALD输注组、Epl治疗组持续输注ALD（1．5ug·h^-1），Epl治疗组同时给予依普利酮（100mg·kg^-1·d^-1）灌胃，对照组、ALD输注组以等量生理盐水灌胃。隔周测量尾动脉压，收集24h尿液测定尿白蛋白排泄率（UAER），于第28天处死动物。PAS染色观察肾组织病理改变，RT—PCR法检测肾素受体表达，免疫组化染色检测肾素受体表达。结果：ALD输注组大鼠血压、UAER较对照组显著升高（P〈0．05），Epl治疗组大鼠血压、UAER显著低于ALD输注组（P〈0．05）；ALD输注组大鼠肾小球系膜细胞增殖伴系膜外基质增多，Epl治疗组肾小球病理变化较ALD输注组显著减轻；肾素受体主要分布于肾小球系膜细胞，Epl治疗组肾素受体mRNA显著低于ALD输注组（P〈0．05）。结论 依普利酮能显著减少ALD输注大鼠肾脏肾素受体表达，减轻ALD诱导的大鼠肾脏损伤。

Effects of Eplerenone on Renal Expression of Renin Receptor in Aldosterone-Infused Rats

Objective： To investigate the effects of eplerenone on renal expression of renin receptor（RnR） in aldosterone-infused rats. Method： Eighteen Sprague-Dawley rats were randomly divided into 3 groups ： normal control group, aldosterone infusion group and eplerenone -treated group. All the rats were subcutaneously embedded with osmotic minipumps, Rats in aldosterone infusion group and eplerenone-treated group were treated with aldosterone （ 1.5ug·h^-1） or aldosterone （ 1.5 ug·h^-1 ） ＋ Eplerenone （ 100mg· kg^-1· d^ -1 ） respectively for 4 weeks. The normal control group was treated with sodium chloride in intragastric administration. The systolic blood pressure,urinary albumin excretion rate（UAER） were measured every 2 weeks. The expression of RnR was detected by RT-PCR and immunohistoehemistry （IHC）. Renal morphological changes were evaluated by light microscopy. Result： Aldosterone-infused rats developed hypertension,renal injury and proteinuria, which could be reversed signifieantly by eplerenone treatment. Expression of RnR was increased remarkably in aldosterone-infused rats compared with normal rats （ P 〈 0.05 ） , However eplerelone treatment apparently decreased the expression of RnR when eompared to aldosterone-infused rats （ P 〈 0.05 ）. Conclusion： The eplerenone prevents aldosterone-incuced renal damage via modification of RnR expression.