Protective effect of losartan on kidney of diabetic rats

Objective: To observe the protective effects of losartan against renal lesion in diabetes mellitus of rats.Methods: The diabetes mellitus Sprague Dawley rats was induced by streptozotocin. The diabetic rats were randomly divided into three groups:normal control group,diabetic model group and losartan treatment group.At the end of the 12th week,the plasma concentration of homocysteine(Hcy) was detected by HPLC method.The mass index of kidney,blood sugar,urea nitrogen,serum creatinine and urinary albumin excretion rate(UAER) were detected by convintional methods.AngiotensinⅡ(AngⅡ) in renal tissue was detected by radioimmunoelectrophoresis.Connective tissue growth factor(CTGF) in renal tissue was detected by immunohistochemical method and ultrastructure of kidney was observed under transmission electron microscope.Results: At the end of the 12th week,the plasma concentration of Hcy,the expression of CTGF in renal cortex,the blood sugar,UAER, urea nitrogen,serum creatinine,mass index of kidney and AngⅡ were significantly increased in diabetic model rats,and the ultrastructure of kidney was noticeably changed.The above indexes in losartan treatment group were significantly lower than those in diabetic model group(P0.01),and changes of kidney ultrastructure were improved.Conclusion: Losartan can reduce diabetic nephropathy through reducing plasma concentration of Hcy,decreasing the level of AngⅡ in the renal tissue,and down regulating the expression of CTGF.In other words,losartan has obvious protective effects on morphology and function of diabetic rats.So it is worthy of further study.