Abstract: Objective To observe the effect of amiloride on the proteinuria of the 5/6 nephrectomy rats. Methods To establish the
5/6 nephrectomy rats model and divide the experiment into 3 groups, sham operated group(Sham), 5/6 nephrectomy model
group(NTX) and 5/6 nephrectomy with amiloride-treated group (NTX + amiloride, n=15). The concentration of protein and
mRNA of uPAR and the change of podocytes motility were detected by coomassiebluestaining, immunofluorence method and
real-time PCR. Results At second week, compared with Control group, the 24 h urine protein of NTX group was significantly
increased (47.50 ± 28.05 mg vs 14.28 ± 3.8 mg, P=0.023). There was no statistical significance in 24-hour urine protein between
NTX+amiloride group and NTX group (51.56±21.03 mg vs 47.50±28.05 mg, P=0.748). The same situation was also observed at
the time point of 12 week, comparing with NTX group, 24-hour urine protein decreased in Sham group (188.31±29.82 mg vs
21.32±8.59 mg, P=0.000) and NTX+amiloride group (188.31±29.82 mg vs 121.37±31.14 mg, P=0.000), with statistical significance
when comparing with Sham group, the expression of uPAR mRNA in NTX group was significantly increased (9.74 ± 1.44 vs
1.01±0.13, P=0.000). In contrast, the expression of uPAR mRNA in NTX rats treated with amiloride was significantly lower than
in NTX group (9.74±1.44 vs 5.01±1.36, P=0.000). Conclusion Amiloride can reduce the proteinuria of the 5/6 nephrectomy rats
model of transient proteinuria by inhibiting the induction of uPAR expression.