The Experimental Study On The Protective Effect And Mechanisms Of Melatoninin Rats Kidney With Renovascular Hypertension

【Objective】To investigate the blood pressure regulation and the protective effect of melatonin in renovascular hypertension model in Wistar albino rats by placing a renal artery clip (two-kidney,one-clip; 2K1C).【Methods】2K1C hypertensive rats were divided randomly into hypertensive group and MLT group.Sham rats were as negative controls.Each group had 8 rats. The rats of MLT group received melatonin (10 mg/kg/day) or vehicle for the following 8 wk. Measurement the blood pressure with Non-invasive Blood Pressure Monitor at 0,2,4,8wk. 24 hour urinary protein (Upro),serum creatinine(Scr),renal tissue SOD activity and MDA content were assayed, semi-quantitative analysis of renal pathology injury,The expression levels of hemeoxygenase-1 (HO-1) and Intercellular adhesion molecule-1(ICAM-1) protein and gene were determined using Immunohistochenistry and real-time PCR.【Results】Compered with sham group,the blood pressure,Upro,Scr,renal tissue MDA content of hypertensive group were significantly increased,while SOD activity were increased(P<0.01), the expression of HO-1 were decreased(P<0.01) and ICAM-1 were increased(P<0.01), at the same time,the injury of the kidney histopathologic were sever; MLT treatment not only decreased the blood pressure,but also improved Upro, Scr, renal tissue MDA content and SOD activity in MLT group with upregulating espression of HO-1(P<0.01)and downregulating expression of ICAM-1(P<0.01),also,it can significantly decreased the degree of renal injury.【Conclusion】Melatonin can reduced the blood pressure and protected against renovascular hypertension-induced tissue damage.The mechanism presumably partly due to lessen the oxidative stress.