Objective: To explore the potential role of substance P receptor (SPR) in the initiation and development of allergic rhinitis (AR).
Methods: Twenty healthy rats were randomly divided into two groups. A model of allergic rhinitis in rat was established by using ovalbumin intraperitoneal immunization and nasal antigen challenge. The nasal mucosa obtained from seven out of ten AR models as well as ten normal controls were studied routinely by HE and immunohistochemical staining to observe the distribution and changes of SPR.
Results: The study showed that immunoreactivity to SPR was present both on the surface and in the cytoplasm of epithelial cells, eosinophils, glandular cells and its ducts, mast cells, plasmocyte and other monocytes. During nasal hypersensitiveness, the staining density and the positive staining cells increased significantly as compared with those in normal controls.
Conclusion: The increase of SPR in nasal mucosa in rat AR model indicates that SPR might play a critical role in the development of AR.