RESUMO
Objective To investigate the role of losartan in AT2-R mediated renal protective effects in renovascular hypertension rat. Methods Male SD rats were divided into sham group and renovascular hypertension group in which Goldblatt methods were performed. The two groups were intragastically administered with losartan (respectively 0, 10, 20, 30 mg?kg-1?d-1) for 6 weeks. Then renal function was measured, the AT2-R expression in the non-ischemic kidney and the AngⅡ contents in non-ischemic kidney and plasma were determined. Results In renovascular hypertension rats, especially in the contralateral, non-ischemic kidney, the expression of AT2-R protein were up-regulated. Losartan increased the AngⅡ contents in non-ischemic kidney and plasma, mediated the natriuretic/diuretic effect and renal protective effect in renovascular hypertension rat and increased the expression of renal AT2-R. Conclusion In renovascular hypertension rat, losartan mediates renal natriuretic/diuretic effect and protects renal function through up-regulating AT2-R in kidney.