ObjectiveTo study the effect of gammasecreta inhibitor(GSI) DAPT on the development of allergic rhinitis (AR) via observing the pathological changes of nasal septum mucosa, the expression of serum IgE, Notch signaling pathway related genes as well as Th cytokines (IL4, IFNgamma) in model mice with AR.MethodsThirtytwo BALB/c mice aged 7-8 weeks were randomly and equally divided into four groups: AR group, DAPT group, control group and dimethyl sulfoxide (DMSO) group. The pathological changes of nasal mucosa in different groups were observed and compared. The expressions of Notchrelated genes in nasal septum mucosa, specific IgE levels in peripheral serum as well as the expressions of cytokines (IL4, IFNγ) in peripheral serum and nasal lavage supernatant were detected.Results①The pathological damage of nasal septum mucosa in DAPT group was significantly mild compared with that in the AR group. ②The serum specific IgE antibody concentration in DAPT group was significantly lower than that in the AR group (P<0.05). ③Reverse transcriptionpolymerase chain reaction (RTPCR) results revealed that the mRNA expressions of Notch1, Notch3 and Notch 4 in nasal septum mucosa of the DAPT group were lower than those of the AR group, and the differences were all statistically significant (all P<0.05). On the contrary, the mRNA expression of Notch 2 in nasal septum mucosa of the DAPT group was higher than that of the AR group, and the difference was also statistically significant (P<0.05). ④Cytokine assay showed reduced expression of IL4 and increased expression of IFNγin both peripheral serum and nasal lavage supernatant of the DAPT group compared with the AR group, and the differences were statistically significant (all P<0.05).ConclusionsDAPT can improve the pathological damage of nasal septum mucosa and reduce the expression of specific IgE in serum of AR mice. DAPT can affect the transcription of Notch signaling pathway related genes, promote the differentiation of Th0 cells into Th1, and further affect the occurrence and development of AR.