Allergic rhinitis animal model induced by cockroach in guinea pigs.

AIM: To establish a cockroach allergen induced allergic rhinitis animal model in guinea pigs.METHODS: Twenty-four guinea pigs were randomly assigned into A,B and C groups.Group A and group B were immunized intraperitoneally with cockroach allergen at the doses of 50 and 100 μg per animal.Group C served as control,immunized with 90 mg/L NaCl.On the 10th and 14th day,all the guinea pigs were immunized for intension by the method as described above.On the 21st day,the nasal cavity of the guinea pig was challenged to sensitize with cockroach allergen once a day for 5 days.At the end of challenge,the anima1 behaviors were evaluated.The histopathology and nasal secretion smear of the animal nasal cavity were also observed.RESULTS: Symptoms of allergic rhinitis,such as sneezing,itching and rhinorrhea were observed in group A and group B(score>5).Pathological examination showed obvious edema and vasodilation.Infiltrations of inflammatory cells mainly composed of eosinophils and mast cells were visible on lamina propria.Compared with that in control group,the number of eosinophils in the epithelium increased significantly(P<0.01).Between group A and group B,significant difference was found in the number of eosinophils in lamina propria of nasal mucosa and nasal secretion(P<0.01).CONCLUSION: Cockroach allergen successfully induces allergic rhinitis model of allergic rhinitis in a dose dependent manner.Cockroach allergen at a high dose is more effective in inducing nasal allergic inflammation,which proves to be a useful tool for the diagnosis,therapy and study of allergic rhinitis.