Objective To investigate renal hypertension associated with renal failure by ligating different branches of the left renal artery in rats and to assess the related serum biochemical indicators.Methods Rats underwent ligation of the posterior branch(n=10) or the anterior and middle branches(n=10) of the left renal artery followed by right nephrectomy.Another 10 rats served as controls.Eight weeks after the operation,tail cuff blood pressure(BP) was measured and the rats were sacrificed using decapitation with the serum samples obtained for the measurement of serum angiotensin II(AII) and endothelin(ET) by radioimmunity.Results BP,serum AII,ET,AST,GLU,CHOL,BUN and CREA levels,as well as quantity of 24 hours' urinary protein of rats in the two operation groups were significantly higher than those in the(control group,while no significant difference was observed between the two operation groups.As for serum ALT,ALB and Trig,no significant difference was observed between the operation groups and the control group.Conclusions(1)A rat model of renal hypertension associated with renal failure can be successfully established using the two operative methods with no difference in related to serum biochemical indicators;(2)It is more convenient to establish a rat model of renal hypertension associated with renal failure by ligating the anterior branch of the left renal artery with a dorsolateral approach;(3)Renal arterial stenosis may cause an increase in serum AII and ET levels,which may play an important role in causing renal hypertension and accelerating renal failure.