Abstract: Objective To explore Aliskiren on transdifferentiation of renal tubular epithelial cells (HKC) induced by TGF-β₁ and to evaluate its effect on platelet derived growth factor(PDGF-BB)、vascular endothelialgrowth factor (VEGF) expressing change.Methods HKC were divided into four groups and cultured for 24 hours in different conditions separately:Serum free as control, Treated with Aliskiren(1.0×10^-7 mmol/L);Treated with TGF-β₁(8 ng/ml); Treated with TGF-β₁ plus Aliskiren in the same concentration. The expression of α-SMA was assessed with RT-PCR, the expression of PDGF-BB、VEGF was assessed with RT-PCR and immunohistochemistry after 24 hours.Results There are little expression of PDGF-BB, VEGF and α-SMA mRNA in control group. Compared with the control group, The expression of PDGF-BB and α-SMA mRNA was markedly increased in HCK cultured with TGF-β₁ group (P<0.05),which were suppressed significantly in HKC cultured with TGF-β₁ plus Aliskiren group (P<0.05). but there are no significant changes in the expression of VEGF between different groups(P>0.05).Conclusions Aliskiren may inhibit transdifferentiation of tubular epithelial cells induced by TGF-β₁ and reduce the expression of PDGF-BB. The inhibition of Aliskiren on transdifferentiation of tubular epithelial cells may be related to the down-regulation of PDGF-BB. It is not very clear on the effect of the expression of VEGF.