Figure 2

Inhibitory effect of sildenafil on hypoxia-induced human PASMC proliferation. Human PASMC were cultured with SMBM (2% FBS) in normoxia or hypoxia in the presence of different concentrations of sildenafil (0 nM, 10 nM, 50 nM, 100 nM) for 72 h. A: Cell viability was measured by MTT. n = 5, ^## P < 0.01 vs. normoxia, * P < 0.05 vs. hypoxia + 0 nM sildenafil. B: 4',6-diamidino-2-phenylindole (DAPI) staining of human PASMC under normoxia or hypoxia with sildenafil (100 nM) for 72 h. a: Image of DAPI stained human PASMC nuclear. b: Summarized data of DAPI stained cell numbers (the average of 3 high power field in every slide).^## P < 0.01 vs. normoxia, ** P < 0.01 vs. hypoxia.