Nitric Oxide Synthase in the Nasal Mucosa

Abstract

Objective: The amount of nitric oxide (NO) in the nasal cavity is significantly higher in allergic rhinitis patients than in healthy individuals. The purpose of this study was to identify NO synthase (NOS) isoforms (NOS-1, NOS-2, and NOS-3) and examine their localization, gene expression, and protein expression in allergic rhinitis model mice.

Method: Male BALB/c mice were intraperitoneally administered Cryptomeria japonica 1 (Cryj1) and adjuvant (primary immunization) 3 times; thereafter, Cryj1 was administered daily into the nasal cavity (secondary immunization). The expression of NOS-1, NOS-2, and NOS-3 in the nasal mucosa was investigated using real-time polymerase chain reaction, and Western blot analysis.

Results: The expression of NOS-1 mRNA was significantly decreased, and NOS-2 and NOS-3 mRNA levels were significantly increased in the allergy group compared to the control group. Protein expression of NOS-1 was significantly decreased and that of NOS-2 was significantly increased in the allergy group compared with the control group, but no significant difference was noted in the levels of NOS-3 protein.

Conclusion: This study shows that not only NOS-2 but also NOS-1 and NOS-3 are involved in the pathogenesis of allergic rhinitis.