[Immunohistochemical and pathological study of capsaicin in the treatment of rabbit animal model with allergic rhinitis].

OBJECTIVE

To determine the desensitization effect of capsaicin.

METHODS

Toluene-2,4-diisocyanate(TDI) sensitized white rabbits used as animal models of allergic rhinitis were treated with capsaicin. At the end of treatment, the changes in the nasal mucosa were studied by immunohistochemical and pathological methods.

RESULTS

Our results showed that the symptoms of allergic rhinitis were remarkably relieved after capsaicin treatment. Immunohistochemical study revealed that substance P immunoreactive fibers in the nasal mucosa showed a marked decrease after capasicin application, but the density and number of SP-IR fibers were significantly increased in the control group. Hematoxylin and eosin staining demonstrated that no edema was found in the nasal mucosa and small vessels were normal after capsaicin application, but edema, vasodilation and inflammatory cell infiltration were discovered in the control group.

CONCLUSION

The results suggested that local capsaicin treatment was a selective, and non-traumatic method to induce a long lasting desensitization of the nasal mucosa, to alleviate nasal congestion, rhinorrhea and sneezing, and to reduce the sensory neuron sensitivity of the mucosa.