The correlation between upper and lower respiratory inflammation

Abstract

Rationale To evaluate the correlation between upper and lower respiratory inflammation. Methods 30 rats were randomly divided into allergic rhinitis group (AR), asthma group (AS), and control group (Con). The pulmonary function was measured by animal pulmonary function instrument, eosinophils and mast cells were detected by hematotoxylin-eosin staining (HE staining) and toluidine blue staining respectively, the expression of VCAM-I and IL-13 in nasal mucosa and lung tissue were examined by immunohistochemistry. ELISA was used to measure the concentration of IL-5 in the peripheral serum. Results The numbers of eosinophils and mast cells in nasal mucosa and lung tissue of AR were both significantly higher than those of Con, and similar results were observed between AS and Con. The forced expiratory volume in 0.3 second (FEV0.3)/forced vital capacity (FVC) of AR and AS was both significantly lower than that of Con. Thenumbers of VCAM-I and IL-13 positive vessels in lung tissue of AR were both significantly higher than those of Con, and similar results were observed between AS and Con. The concentration of IL-5 in the serum of AR and AS was both significantly higher than that of Con. The concentration of IL-5 in serum was positively correlated with the number of eosinophils in peripheral blood of AR and AS. Conclusions The inflammation is similar between AR and AS. Repeated challenging upper respiratory in allergic rhinitis models can result in the expression of VCAM-I and IL-13 in nasal mucosa and lung tissue, which may induce infiltration of eosinophils into lung tissue and result in reduction of FEV0.3/FVC.