Objective      To study Trps1 expression changes in rat kidney after ischemia/reperfusion (I/R) injury and its relationship with renal pathological changes so as to explore the role of Trps1 in renal repair and regeneration.       Methods      Forty-two male SD rats were divided to a sham operation group and an I/R group. Kidney I/R rat model was established by clipping bilateral renal pedicles by artery clamps for 60 min after isolating them from surrounding tissues. On days 1

3

7

14 and 21 after kidney I/R

SCr and BUN were detected. Renal injury was observed under a light microscope with PAS staining

and Trps1 was tested by immunohistochemistry and Western blotting.       Results      The SCr and BUN levels in the sham operation group were (30.12±2.95) μmol/L and (5.89±0.67) mmol/L. The levels of SCr [(319.25±25.49)

(338.20±22.70)

and (216.07±18.54) μmol/L] and BUN [(33.53±8.06)

(78.05±7.13)

and (42.61±11.87) mmol/L] on days 1

3

and 7 were significantly higher in the I/R group than in the sham operation group (P0.05). No significant difference was observed in SCr [(33.33±6.46) and (32.06±8.74) μmol/L] and BUN [(6.02±1.27) and (6.93±3.28) mmol/L] levels between the two groups on days 14 and 21 (P0.05). PAS staining results showed that kidney injury started on day 1 and was the severest on day 3

while kidney repair started on day 7 and completed on day 21. Immunohistochemistry results showed that Trps1 was mainly expressed in kidney tubules of cortex in the sham operation group. In the I/R group

Trps1 expression in kidney tissue decreased significantly on day 1 after I/R (P0.05)

was weak on day 3 (P0.05)

started to increase on days 7 and 14 but still had significant difference (P0.05)

and returned to the same level as the sham operation group on day 21 (P0.05). The expression of Trps1 was negatively correlated with kidney tubule injury (P0.05).       Conclusion      Trps1 shows upregulated expression during kidney repair after acute kidney injury

and is negatively correlated with injury degree. Trps1 may play a positive role in kidney repair.