Objective:To investigate the expression of TLR4 protein and NF-κBp50 protein after renal ischemia-reperfusion and study their significance in renal ischemia-reperfusion injury.Methods:48 normal male Sprague-Dawley rats were randomly divided into two groups:control group(C group)and ischemia-reperfusion group(Ir group).The renal ischemia-reperfusion injury model was established by clamping the left renal artery for 45 min and reperfusion for 6

12

24 h and 72 h

then the right kidneys were removed before clamping left renal vessels.Two-step immunohistochemical methods were used to detect the changes in the expression of TLR4 protein and NF-κBp50 protein.Myeloperoxidase(Mpo) activity and serum creatinine(Scr) levels were determined

which reflected neutrophil activation and kidney dysfunction.Results:The Mpo activity and the Scr levels were increased remarkably in Ir group

as compared with C group(P<0.01).The expression of TLR4 protein and NF-κBp50 protein were gradually increased with the progress of ischemia-reperfusion(P<0.01).Conclusion:The occurrence of renal ischemia-reperfusion injury may correlate with the inflammatory response induced by TLR4 activating NF-κB.