地塞米松对哮喘模型豚鼠肺泡灌洗液IL-4、IFN-γ水平及肺组织NF-κB的影响

目的：探讨地塞米松对支气管哮喘豚鼠模型肺泡灌洗液（BALF）中IL-4、IFN-γ水平及肺组织中NF-κB的影响。方法：实验分为正常对照组、哮喘模型组、地塞米松治疗组。用卵白蛋白（OVA）致敏、激发建立哮喘豚鼠模型。ELISA法检测豚鼠BALF中IL-4，IFN-γ含量。免疫组化法观察NF-κB在豚鼠支气管上皮的表达。结果：哮喘组BALF中的IL-4、IFN-γ含量及PC20水平都与正常对照组有显著差别（P〈0．05），而地塞米松治疗组豚鼠BALF中IL-4含量明显低于哮喘模型组（P〈0．05），其IFN-γ含量和PC20水平较后者显著升高（P〈0．05）。哮喘模型组和地塞米松治疗组豚鼠气道中NF-κB阳性细胞百分比有显著差异（P〈0．05）。结论：地塞米松能有效降低豚鼠BALF中IL-4水平，升高IFN-γ含量，同时降低气道高反应性和NF-κB在哮喘豚鼠支气管上皮中的表达。

Effects of dexamethasone on IL-4 and IFN-γ in bronchoalveolar lavage fluid and NF-κB in lung tissue of asthmatic model in guinea pigs

Objective ：To explore the effect of dexamethasone on IL - 4 and IFN - γ in bronchoalveolar lavage fluid （BALF） and NF- κB in the lung tissue of asthmatic model in guinea pigs. Methods： This experiment included normal control group, asthmatic model group, dexamethasone treatment group. Asthmatic models of guinea pigs were constructed by immunization and challenged with nebulized OVA. The levels of IL -4 and IFN - γ in BALF of guinea pigs were determined by using enzyme - linked immunosorbent assay （ ELISA ）. The expression of NF - κB in the lung tissue was observed by immunohistochemical staining. Results： In the asthmatic model group, the levels of IL - 4 and IFN - γ in BALF and PC20 had significant differences compared with those of normal control group, respectively （ P 〈 0.05 ）. The levels of IL - 4 in BALF of dexamethasone groups were significantly lower than those of asthmatic model group （ P 〈 0. 05 ）. But the levels of IFN - γ and PC20 in dexamethasone groups were significantly higher than those of asthmatic model group （ P 〈 0.05 ）. The percentage of NF- κB positive cells in asthmatic model group had significant difference compared with dexamethasone group （P 〈 0.05）. Condusion： Dexamethasone can effectively decrease the levels of IL -4 and increase IFN -γ in BALF, it can decrease airway hyperresponsiveness and expression of NF - κB in the asthmatic guinea pigs.