FIGURE 4.

Growth differentiation factor 8 (GDF8) increases the phosphorylated protein levels of SMAD2 and SMAD3 in HTR8/SVneo and primary EVT cells. HTR8/SVneo (A,B) or primary EVT (C,D) cells were treated for 30 or 60 min with the vehicle control (Ctrl) or 25 ng/mL GDF8. The phosphorylated protein levels of SMAD2 (A,C) and SMAD3 (B,D) were examined using western blot analysis. SMAD2 and SMAD3 were used as the loading control and references for densitometric analysis for p-SMAD2 and p-SMAD3, respectively. The results are displayed as the mean ± SEM of at least three independent experiments, and the values with different letters are significantly different (P < 0.05).