Qom University of Medical Sciences Journal

Background and Objectives: Activation of AT1 receptor (type 1 angiotensin II receptor) has an important role in the pathogenesis of renal ischemia-reperfusion injuries. In the present study, the effect of losartan on the level of reactive nitrogen species (RNS) and renal function in renal ischemia-reperfusion injuries, was assessed in rat.

Methods: Eighteen male Wistar rats were randomly divided into three groups of sham, control ischemic, and ischemic treated. Ischemia was induced by occlusion of renal arteries for 60 min. Losartan (10mg/kg) were injected intraperitoneally one hour before ischemia, and also 24, 48, and 72 hours after ischemia. Blood samples were collected for measuring creatinine before and 72 hours after ischemia. Finally, NOx concentration and histopathological changes were assessed 72 hours after ischemia.

Results: The mean of creatinine concentration in the animals in sham and control ischemic groups at the beginning of experiment were 0.37±0.21 and 0.27±0.14mg/dl, respectively. Induction of ischemia significantly increased creatinine concentration (2.75±2.26mg/dl) in the control ischemic group (p=0.020). The NOx concentration significantly increased in control ischemic group (29.49±5.93nmol/mg protein) compared to sham group (1.00±0.23nmol/mg protein), (p>0.001). Losartan significantly decreased the concentration of creatinine (0.68±0.52mg/dl) in the ischemic treated group (p=0.044), and considerably decreased the NOx level in ischemic treated animals along with histhopathological altrations (53%).

Conclusion: The use of losartan can effectively prevent renal ischemia-reperfusion injuries through reduction of RNS and improve the function of the ischemic kidney.