Smad7 expression in UUO kidneys. (A) Western blot analysis of Smad7 in renal extracts collected from UUO kidneys at indicated days after operation, showed a gradual reduction of Smad7 content in UUO kidneys compared with sham-operated kidneys. (B) Densitometric analysis of Smad7 protein levels detected by Western blot analysis. Significant decreases of Smad7 protein were noted in UUO kidneys (filled bars) compared with sham-operated kidneys (open bar). (C) Total RNA was subjected to real-time RT-PCR for measurement of Smad7 mRNA and GAPDH mRNA (internal control) levels. Data are ratios of Smad7 mRNA/GAPDH mRNA in sham-operated kidneys (open bar) and UUO kidneys (filled bars) on days 7, 14, and 28. In contrast to Smad7 protein, Smad7 mRNA expression was up-regulated significantly in UUO kidneys compared with sham-operated kidneys. Data are given as mean ± SEM values of nine mice in each group. *, P < 0.05, compared with sham-operated kidneys.