Abstract:

Objective To establish  allergic rhinitis (AR) models of Wistar rats,and to discuss the pathogenesis of  allergic inflammation of respiratory tract,and to provide basis for clinical treatment of AR.Methods 30 Wistar rats were randomly divided into model group(n=10),normal group(n=10) and dexamethasone(DEX) group(n=10).The rats in model group were immunized intraperitoneally with ovalbumin(OVA),followed by intranasal administration of OVA;and the rats in normal group were adminstrated with saline instead of OVA;the rats in DEX group were challenged into AR,then they  were injected with 0.2 mL/kg dexamethasone muscle of hind legs.The behavioral symptoms,histological changes of  nasal mucosa,the number of eosinophile granulocytes and the expression levels of IgE were detected by HE staining and immunohistochemical methods. Results The AR symptoms,such as nasal itching,sneezing,and rhinorrhea of the rats  in model group were observed.There were a lot of histological changes,such as eosinophile granulocytes,lymphocytes,edema of the mucosa,gland hyperplasia,strong secretion,and cilia destruction on nasal surface of the rats in model group.There were only mild grasping nose and a small amount of sneezing of the rats in normal group.The small blood vessels of the rats in DEX group had no significant expansion,the mucosal thickness was lower than that in model group and the degree of inflammatory cell infiltration  was alleviated.The numbers ofeosinophile granulocytes and their A values of the rats  in  DEX group and model group were higher than those in nomal group(P<0.05).The number of eosinophile granulocytes  and its A value of the rats in  DEX group were lower than those in model group(P<0.05).Conclusion The   AR rat model  induced by OVA is established successfully.

Key words: allergic rhinitis, disease model,animal;ovalbumin;eosinophile granulocytes;immunoglobutin