Figure 2.

Effect of sildenafil on lung function, emphysema development and lung interstitial abnormality. Lung function quantified by peak expiratory flow (PEF), 50% tidal volume expiratory flow (EF50) and tidal volume (VT) was shown in (A1), (A2), and (A3). Emphysema evaluated by mean linear intercept (MLI) and mean alveolar numbers (MAN) was shown in (A4) and (A5). The above data were presented as mean ± SD; n = 10/group; *p < 0.05 vs. model group); **p < 0.01 vs. model group. Representative photomicrographs of emphysema development stained by hematoxylin and eosin stain were shown in (B1, B2, and B3) with scale bars = 160 μm, and in (C1, C2, and C3), with scale bars = 40 μm. Representative photomicrographs of interstitial abnormality stained by Van Gieson stain were shown in (D1, D2, and D3) with scale bars = 160 μm and in (E1, E2, and E3) with scale bars = 40 μm.