Abstract: AIM: To build an allergic rhinitis model to evaluate the effect of budesonide on the eosinophils and histamine in nasal mucosa in allergic rhinitis guinea pig.METHODS: 33 guinea pigs were randomly divided into three groups:natural controlled group , allergic rhinitis (AR)group and budesonide treatment group.Allergic rhinitis model in guinea pigs were built by using toluene-2 , 4-disocyanate (TDI) nasal immunization and challenge.The indexes of clinical symptoms , pathomorphological diagnosis and content of histamine in mucosa were used to evaluate the potency of budesonide when used to treat allergic rhinitis.RESULTS: The expression of eosinophils and the content of histamine in nasal mucosa in AR group both were significantly higher than that of in natural controlled group (respectively ,P<0.01 and P<0.05).After the treatment , the expression of eosinophils and content of histamine in guinea pigs nasal mucosa were significantly decreased (bothP<0.01)compared with the AR group.The point rating of clinical symptoms of guinea pig nasal in both AR group and treatment group were higher than that of in natural group (P<0.01).However , there was no difference between AR group and treatment group (P>0.05).CONCLUSION: Budesonide could effectively reduce the expression of eosinophils and content of histamine in nasal mucosa ,but it is invalid in releasing the symptoms of AR in guinea pig.The reason of this phenomenon may be concerned with the method of model building.

Key words: budesonide, allergic rhinitis, eosinophils, histamine