Objective      To explore the impact of urokinase (UK) on improving the renal function of rabbits with long-time warm ischemia (WI).       Methods      Thirty rabbits were randomly divided into 3 groups: sham operation (SO) group

WI group

and WI+UK group. WI rabbit model was established by clipping both left renal artery and left renal vein for 90 min. Renal in situ autografting model was simulated by HCA liquid cold perfusion and then blood reperfusion. Serum creatinine (Cr) was examined in each group. Pathological sections were observed by HE staining and Masson staining. Thrombomodulin (TM) expression was analyzed by immunohistochemistry (IHC).       Results      On the 35th day after the operation

the Cr level was greatly increased in the WI group and the WI+UK group than the SO group (P0.05)

while the Cr level (118.99±17.18 μmol/L) of the WI+UK group was significantly lower than (165.34±8.38 μmol/L) of the WI group (P0.01). In the WI group

a large amount of micro-thrombi appeared in the glomeruli

and very severe edema and necrosis were found in the kidney tubules

but in the WI+UK group

there was no abnormality in the glomeruli and kidney tubules. The TM expression of the WI group was greatly higher than that of the SO group (P0.05)

and the TM expression of the WI+UK group was significantly lower than that of the WI group (P0.05).       Conclusion      Obvious micro-thrombi are observed after 90-min WI

which leads to destroy of kidney structure and decrease of kidney function. After treatment with UK

the micro-thrombi are dissolved

and the kidney structure and function are recovered.