Abstract: Objective To investigate the therapeutic effect of Losartan on ADM, ET-1 and their receptors in the kidney of diabetic rats. Methods Experimental diabetes were induced in uninephrectomized rats by STZ. The animals were divided into three groups: group A (control group), group B (diabetic group) and group C (Losartan-treated group). Immunohistochemistry, western bloting, in situ hybridyzation and RT-PCR were used to detect the protein and mRNA expressions of ADM, ADMR, ET-1 and EDNR-A. Results Compared with group A, the expressions of ADM, ADMR, ET-1 and EDNR-A in group B distinctly increased. After Losartan treatment, those debased. Conclusions The expressions of ADM, ET-1 and their receptors may be responsible for the renal protective effect of Losartan in diabetic rats.