Inhibition of rhinorrhea with botulinum toxin type A and the expression of VIP on nasal mucosa in allergic rhinitis rat

    WEN Weiª²Dong1, HOU Yiª²Ping1, YUAN Fang1, WANG Yinª²Chun2, SONG Yanª²Feng1

    1Department of Anatomy, Lanzhou Medical College, Lanzhou 730030, China, 2Lanzhou Institute of Biological Products, Lanzhou 730046, China

    ¡¾Abstract¡¿ AIM: To study the effect of Botulinum toxinª²A (BTXª²A) on inhibition of rhinorrhea, expression and morphological change of Vasoactive intestinal polypeptide (VIP) at nasal mucosa, in allergic rhinitis (AR) rats. METHODS: Ovalbumin sensitized the rat to establish allergic rhinitis model. Rats were divided into control group (n=6), allergic group (n=10), allergic rats treated with BTXª²A (AR+BTXª²A) group (n=5). VIP immunoreactivity at nasal mucosa in the allergic rhinitis rats was studied by immunohistochemistry. The morphological changes at nasal mucosa were observed by histological staining methods. RESULTS: The symptoms of allergic rhinitis, nasal rhinorrhea and sneezing, were remarkably augmented after ovalbumin application. The nasal rhinorrhea symptom diminished after BTXª²A treatment. The quantity of nasal secretion was significantly reduced in (AR+BTXª²A) group as compared with that in allergic group (P©‚0.05). The nasal sneezing symptom in AR+BTXª²A group was not significantly different with that in the allergic group. Hematoxylin and eosin staining demonstrated that no edema, small vessels were found in AR+BTXª²A group, but edema, vasodilational and inflammation cell infiltration were observed in the allergic group. Immunohistochemical study revealed that VIP immunoreactive fibers at the nasal mucosa decreased markedly after BTXª²A application, but a large number of VIP fibers were observed in the allergic group. CONCLUSION: Local BTXª²A treatment is a selective and nonª²traumatic method to reduce a long lasting desensitization of the nasal mucosa ......