ABSTRACT
Objective To observe the expression of leptin(Lep) receptor (LepR) and aquaporin 2 (AQP2) in the kidneys of obesity-related hypertensive rats ( OHR ) and to explore the mechanism of Lep resistance and water metabolic disorders in them.Methods OHR( model group) were induced by high-fat diet.Normal Wistar rats were chosen as normal control and hypertensive rats(SHR) as positive control.The serum level of triglycerides(TG), total cholesterol(TC), Lep, vasopressin ( AVP ) , angiotensinⅡ( AngⅡ) and β2-microglobulin (β2-MG ) was measured by enzyme linked immunosorbent assays ( ELISA) and renal morphology was observed by HE staining.The density of LepR and AngⅡtype 1( AT1) in the kidney was observed by immunohistochemistry.mRNA And protein expression of LepR and AQP2 in the kidney was assayed by real-time polymerase chain reaction and Western blotting.Results Compared with normal rats,the TG, TC, Lep, AVP, AngⅡand β2-MG of the model group were significantly increased (P<0.05), and protein and mRNA expression of LepR and AQP2 in the kidney were up-regulated (P<0.05).Compared with SHR group, TG, TC and Lep in serum of the model group were significantly increased (P<0.05).The concentrations of AVP,β2-MG and Lep was linearly related(R2 =0.87,R2 =0.95).Conclusion Water metabolic disorder and Lep resistance may be involved in the kidney injury of OHR, which may be one of the important pathogeneses of obesity-related hypertension.