高脂高糖饮食对自发性高血压大鼠水通道蛋白1mRNA表达及对尿钠排泄的影响

Effect of high fat and glucose diet on expression of aquaporin-1 mRNA and excretion of urine natrium in spontaneous hypertensive rats

目的探讨高脂高糖饮食对自发性高血压大鼠(SHR)水通道蛋白1(AQP-1)mRNA与NO表达的影响,及其在加重尿钠排泄中的作用。方法 6周龄雄性SHR 24只随机分为高脂高糖组12只和普通饲料组12只,第8、12周末观察高脂高糖饮食对其NO、尿钠排泄等的影响,并计算肾质量指数。12周末RT-PCR检测肾脏AQP-1mRNA表达。结果与普通饲料组比较,高脂高糖组第8、12周末血压、血浆NO、肾脏尿钠排泄量明显降低(P<0.05),12周末肾组织AQP-1mRNA表达明显降低[(0.54±0.07)vs(1.28±0.39),P<0.01],第12周末肾质量指数明显升高[(3.40±2.00)mg/g vs(2.30±1.00)mg/g,P<0.05]。结论长期高脂高糖饮食可加重SHR肾脏损害,其机制可能与内源性NO合成降低、肾脏AQP-1mRNA表达降低相关。

Objective To study the effect of high fat and glucose diet on expression of aquaporin-1 （AQP-1） mRNA and excretion of urine natrium in SHR.Methods Twenty-four male SHR aged 6 weeks were randomly divided into high fat and glucose diet group （n=12） and normal diet group （n=12）.Effect of high fat and glucose diet on NO synthase and excretion of urine natrium was detected at weeks 8 and 12.The animals were killed at the end of week 12 to harvest the total RNA.Expression of AQP-1 mRNA was detected by RT-PCR.Results The serum NO synthase level,urine natrium excretion volume and AQP-1 mRNA expression level were significantly lower in high fat and glucose diet group than in normal diet group at weeks 8 and 12.Conclusion Long-term high fat and glucose diet aggravates kidney damage in SHR by downregulating their endogenous NO synthesis and AQP-1 mRNA expression in kidneys.