Figure 2.

Lung sections of rats in the three groups. Lung sections from NC, SC, and AA were stained with H&E. (a) In NC, the structure of the alveolar wall was clear and complete without inflammatory cell infiltration in the lungs. (b) In SC, the bronchial wall and the smooth muscle were slightly thickened, and few inflammatory cells infiltrated the interstitium and alveoli of the lung; (c) In AA, the bronchial wall of the rats with asthma was damaged invasively by numerous inflammatory cells, which infiltrated the whole layer of the bronchial wall. The pulmonary alveoli collapsed, the intervals between pulmonary alveoli were widened, and a part of the pulmonary alveoli were dilated.