Histophatologic changes of lung in asthmatic male rats treated with hydro-alcoholic extract of Plantago major and theophylline

Objective: Plantago major (P. major) is one of the medicinal crops in the world which has therapeutic properties for treatment of respiratory and gastrointestinal diseases. Theophylline is commonly used for the treatment of respiratory diseases. In this study, we investigated the protective effects of hydro-alcoholic extract of P. major on lung in asthmatic male rats. Materials and Methods: 32 male adult rats were randomly divided into 4 groups: The control group (C) received normal saline; Asthma (A) group received a normal diet; Asthma group treated with Theophylline (200 mg/kg b.w.) (T); Asthma group which received p.major (100 mg/kg b.w.) (P). Asthma was induced by citric acid, 0.1 mg in form of spraying. The injection of P.major extract and theophylline was administered intraperitoneally for four weeks. At the end of the treatment, all of the rats were sacrificed and lungs were taken out, fixed, and stained with H&E, toluidine blue, and PAS, then histological studies were followed with light microscope. Results: Results showed that, in asthmatic group, the mean number of mast cells was significantly increased (p<0.05). Thickness of alveolar epithelium and accumulation of glycoprotein in airways was increased. Moreover, in some of alveolar sac hemorrhaging was observed. Administration of p.major extract in asthmatic rats restored these changes towards normal group. Conclusion: The present study revealed that P. major compared with theophylline, has a protective effect on lung in asthmatic rats.