Effects of nedocromil sodium on the symptoms and substance Pexpression in nasal mucosa of rabbits with experimental allergic rhinitis

Objective To investigate the effects of nedocromil sodium on the symptoms and the ex- pression of substance P in nasal mucosa of experimental allergic rhinitis (EAR) based on a comparative study carried out among rabbits with the lesion.Methods Experimental allergic rhinitis model was prepared among rabbits with the use of toluene 2,4-diisocyanate (TDI) at first.Then,nedocromil sodium was used to intervene the pathological process of this induced lesion in a local applying way.Followed was a comparative observation on the changes in the symptoms of this condition and the expression of substance P immunoreactive(SP-IR) fi- bers in nasal mucosa of rabbits with the lesion by the procedures of immunohistochemistry before and after in- tervening with the agent.Results Following the intervening with nedocromil sodium,significant reduce in the expression of SP-IR fibers,disappearance of tissue edema and infiltration of inflammatory cells in nasal muco- sa were observed among the animals of intervening group,with the improving in the symptoms and signs of EAR.In contrast,the expression of SP-IR fibers was significantly increased,tissue edema was very severe,and dilation of vessels and infiltration of inflammatory cells were obviously marked in the nasal mucosa of modeling animals as controls.Conclusions Nedocromil sodium can be effectively used to alleviate nasal congestion and such symptoms as rhinorrhea and sneezing,and to reduce the expression of SP-IR fibers in nasal mucosa in the ways of density and contents in the pathological process of allergic rhinitis.