Fig. 4

Histologic evaluation of hematoxylin & eosin, Masson trichrome staining and alpha-smooth muscle actin (αSMA). A, B Loss of epithelial tissue, inflammatory cell infiltration, vascular dilatation and congestion, and extensive submucosal fibrous tissue proliferations were observed in the experimental group (inset, original magnification, × 40). Masson trichrome staining of collagenous fiber (green). The control group represented regular arranged epithelial tissue and sparse connective tissue (inset, original magnification, × 40). C The αSMA-positive was intensively expressed in the submucosal layer of the experimental group than that in the control group on PID 7 (inset, original magnification, × 40). Immunohistochemical staining of αSMA protein (brown)