【摘要】 目的研究高盐对AngⅡ肾脏损伤SD大鼠血压、肾脏组织形态、超微结构以及肾脏骨调素(OPN)表达的影响。方法选取12周龄正常盐饮食雄性SD大鼠36只制作AngⅡ(每分钟给予100ng/kg·b.w.)肾脏损伤模型。之后随机分为高盐(4%NaCl)及正常盐(0.6%NaCl)饮食组(n=18)作为对照组。每2周测量大鼠鼠尾血压,分别于AngⅡ输注2周末及不同盐饮食第12周末每组处死6只。采用免疫组化方法测定大鼠肾脏OPN、TGF-β1表达;荧光定量PCR方法测定大鼠肾脏OPNmRNA表达。光镜下观察肾脏组织形态改变,电镜下观察肾脏超微结构改变。结果输注AngⅡ2周后大鼠血压显著升高,大鼠肾脏TGF-β1、OPNmRNA及其蛋白表达升高,与对照组大鼠比较有显著差异(P<0.05)。停用AngⅡ后大鼠血压恢复正常。继续摄入高盐或正常盐饮食,两组大鼠血压无明显差异(P>0.05)。摄入高盐饮食12周后大鼠肾脏TGF-β1、OPNmRNA及其蛋白表达显著升高,与正常盐饮食及对照组大鼠比较,有显著差异(P<0.01)。形态学观察发现输注AngⅡ对大鼠肾脏造成轻度损伤,继续摄入高盐加重大鼠的肾脏损伤。结论AngⅡ肾脏损伤基础之上,高盐摄入加重了大鼠肾脏损伤,高盐所致大鼠肾脏损伤不依赖于血压升高。OPNmRNA及其蛋白表达增强是肾脏损伤的结果。更多还原

【Abstract】 Objective To investigate the effect of high-salt diet on blood pressure,renal morphology and osteopontin (OPN) expression in Sprague-Dawley rat with AngⅡ-induced renal injury.Methods Thirty-six male SD rats aged 12 weeks receiving normal salt diet were rolled in the study,and received AngⅡ(100 ng·kg-1·min-1) for two weeks using subcutaneous minipump.Rats were then fed high sodium (n=18,4% NaCl) or normal sodium (n=18,0.6% NaCl) diet from third week respectively and lasted for 12 weeks.Eighteen rats in the control were sham-operated and fed normal sodium diet.Tail systolic blood pressure (SBP) was determined every two weeks.Expressions of TGF-β1?OPN mRNA and its protein in SD rat kidney were measured with quantitative RT-PCR and immunohistochemistry respectively at the end of Ang II infusion and at the end of the experiment.Renal ultrastructure was observed by electronmicroscopye.Results SBP of the rats received AngII increased significantly compared with controls (P?0.05).SBP returned to normal after AngⅡ infusion stopped.No significant difference existed in blood pressure between rats fed high salt diet and normal salt diet in the period of 12 weeks (P<0.05).Expressions of TGF-β1,OPN mRNA and its protein in the kidney of the rats fed with high salt diet were up-regulated at the end of AngⅡ infusion (P>0.05) and at the end of the 12th week compared with the rats fed normal salt diet and controls (P<0.01).The kidney was damaged by AngⅡ,which was further aggravated by the infusion of high salt diet.Conclusions High salt diet could aggravate the renal injury of the rats with AngⅡ-induced renal injury that may be independent of blood pressure change.Expressions of the TGF-β1,OPN mRNA and its protein were up-regulated after renal injury.更多还原