The Expression And Significance Of NF-κB And INOS In The Rats With Allergic Rhinitis

ObjectiveIn the study, we examined the number of eosinophile granulocyte (EOS), and theexpression of nuclear factor kappa B (NF-κB) and inducible nitric oxide synthase(iNOS) in the nasal mucosa and lung tissue of the rats with allergic rhinitis. The aimsto investigate the mechanism and significance of NF-κB and iNOS on the pathologicreaction and the consistency of upper and lower airway allergic inflammation.Methods25female SD rats (160~180g body weight) were randomly divided into twogroups,15rats in the allergic rhinitis group (AR group) and10in the control group.The allergic rhinitis group was given eight intraperitoneal injections (Qod) of20mgovalbumin (OVA) and30mg aluminum hydroxide dissolved in1ml normal saline,and then intranasal dripping with5%OVA daily for10consecutive days since16thday,50ul per side, once a day.The control group was treated as the same to the ARgroup but without OVA. The behaviors of the rats were closely observed for30minutes after the last provocation, recorded the behavior scores according to the scorestandard of the allergic rhinitis symptoms in rats, all the scores of a rat more than fivepoints was the building successfully.10%chloral hydrate (0.5ml/100g) wasinjected into abdominal cavity of all the rats after the models were establishedsuccessfully, then these rats were killed in24hours. Soon afterly, nasal mucosa wasseparated from nasal cavity and lung tissue from cavum pectoris, then fixed in4%paraformaldehyde, embedded with paraffin and pathological section was made. Theinfiltration of eosinophile granulocyte was detected by HE staining.Immunohistochemical staining (SP method) was used to determine the expression ofNF-κB and iNOS in nasal mucosa and lung tissue. The correlations between themwere analyzed by statistics. Result1. The behavior observation of all the animal: The typical symptoms of ARincluding rhinorrhea, frequent sneezing, violently scratching nose could be observedin AR group (all scores>5). The control group only appeared mild symptoms such asitching, sneezing and so on (all scores<5).2. HE staining results showed that: Cilia dysfunction, lodging, defluxio, smallvessel appeared expanded in different level, glandular organ hyperplasy, goblet cellproliferation, tissue edema, basement membrane which became thick, the infiltrationof numerous eosinophile granulocyte and lymphocytes, some neutrophils, and a fewof macrophages were revealed in the epithelium and epithelial below; The lung tissuepathological slices showed the bronchial lumen became narrow, bronchial mucosabecame thick, marked infiltration of numerous eosinophile granulocyte andlymphocytes in pulmonary interstitial, but the nasal mucosa and lung tissue of thecontrol group had no these obvious signs of inflammation. Statistic result of thenumber of eosinophile granulocyte in nasal mucosa was10.07±3.67and lung tissuewas9.67±3.50of the AR group, but in control group, the number in the nasal mucosawas1.30±0.95, in the lung tissue was1.20±1.14. The number of eosinophilegranulocyte in nasal mucosa and lung tissue had significant difference between ARand control group (all P <0.05).3. Immunohistochemical staining (SP method) results showed that: The NF-κBpositive expression mainly located in epitheliums, gland cells, vascular endothelialcells and inflammatory cells in nasal mucosa of the AR group, also in bronchialmucosa epitheliums, alveolar epitheliums, vascular endothelial cells, inflammatorycells in lung tissue, and the cytoplasms of positive cells were dyed tan. The iNOSpositive signal mainly located in epitheliums, gland cells, smooth muscle cells,vascular endothelial cells and inflammatory cells in nasal mucosa of the AR group,also in bronchial mucosa epitheliums, alveolar epitheliums, vascular endothelial cells,inflammatory cells in lung tissue, and the cytoplasms of positive cells were dyed tan.Statistic result of the number of NF-κB positive cells in nasal mucosa was 88.87±14.52and lung tissue was82.13±12.02of AR group, but in control group, thenumber in the nasal mucosa was42.00±4.88, in the lung tissue was31.50±6.10. TheNF-κB expression in nasal mucosa and lung tissue had significant difference betweenAR and control group (all P <0.05). Statistic results of the number of iNOS positivecells in nasal mucosa was96.53±17.90and lung tissue was77.87±9.13of AR group,but in control group, the number in nasal mucosa was36.50±7.38, in lung tissue was29.70±5.21. All the number of iNOS positive cells in nasal mucosa and lung tissue ofAR group were obviously larger than that of control group (all P <0.05).4. Analysis of correlation: In AR group, there was a positive correlation betweenthe number of NF-κB and iNOS positive cells in nasal mucosa (r=0.643, P<0.05),also in lung tissue (r=0.553, P <0.05), at the same time there was a positivecorrelation between the number of NF-κB positive cells in nasal mucosa and thenumber in lung tissue (r=0.613, P <0.05), there also was a positive correlationbetween the number of iNOS positive cells in nasal mucosa and that in lung tissue (r=0.551, P <0.05).Conclusions1.The model of allergic rhinitis in SD rats could be established successfully withOVA and aluminium hydroxide, and our experimental results show that there wasconsistency in upper and lower airway inflammation. In clinical work, much attentionshould be paid to the evaluation of the lower airway allergic disease when treatingallergic rhinitis in order to improve the therapeutic effect.2.Eosinophile granulocyte, NF-κB and iNOS can induce pathophysiologicalreaction of the airway allergic inflammation. NF-κB and iNOS may play importantroles in the consistency of upper and lower airway inflammation.