Figure 6. Masson's trichrome staining of lung tissue from rats. (A–C) Representative image of Masson's trichrome staining of lung tissue from control rats, COPD rats with lower β2M and COPD rats with higher β2M, respectively. The right panel shows Masson staining positive area in control rats, COPD rats with lower β2M and COPD rats with higher β2M. P<0.05 in COPD rats with lower β2M versus control and in COPD rats with higher β2M versus COPD rats with lower β2M. Bars represent Means.