Relative mRNA expression levels of SHP, TGF-β, PAI-1, type I collagen, and fibronectin in kidneys of rats with UUO. (A) Representative RT-PCR analysis of SHP, TGF-β, PAI-1, type I collagen, and fibronectin expression in UUO kidneys. Rats were killed at 7 d after UUO. RT-PCR was performed on RNA from three different normal rat kidneys or UUO rat kidneys. (B) Quantification of RT-PCR results expressed as the mean ± SEM of three independent experiments (n = 9 in each group). β-actin protein levels were analyzed as an internal control. *P < 0.001 and **P < 0.01 compared with control.