Figure 6.

Effect of Smad2, Smad3, or double Smad2/3 knockdown on Col1 and Col3 expression after CGS21680 (1 μM) or TGF-β1 (5 ng/ml). A) siRNAs specifically reduce protein expression of Smad2, Smad3, or Smad2/3. Bands were quantified, and data represent means ± se of 8 independent experiments. Statistics were performed by Student's t test. *P < 0.05, ***P < 0.001 vs. control siRNA. B) NHDFs were stimulated for 24 h with the A_2AR agonist CGS21680 (1 μM) or TGF-β1 (5 ng/ml). Statistics were performed by Student's t test. ^#P < 0.05, ^##P < 0.01 vs. nonstimulated control. Data represent means ± se of 4 independent experiments.