糖皮质激素及茶碱对哮喘小鼠气道炎症与肺内一氧化氮抑制作用的研究

The role of glucocorticosteroid and theophylline in asthmatic inflammation of murine model and the inhibition in NO production in lung

目的探讨糖皮质激素、茶碱对哮喘气道炎症和肺内一氧化氮（ＮＯ）水平、诱生型一氧化氮合酶（ｉＮＯＳ）表达的影响。方法ＢＡＬＢ／ｃ小鼠分为６组：哮喘模型组（Ａ，１０只），正常对照组（Ｎ，１０只），地塞米松雾化吸入组（Ｃ１，７只），地塞米松腹腔注射组（Ｃ２，７只），布地奈德气雾剂组（Ｃ３，７只），茶碱组（Ｔ，１０只）。建立哮喘模型，给予糖皮质激素、氨茶碱，观察支气管肺泡灌洗液（ＢＡＬＦ）中白细胞总数、嗜酸性粒细胞百分比（ＥＯＳ％）、总蛋白水平及ＮＯ水平的变化，用ＮＡＤＰＨｄ组化法和ｉＮＯＳ免疫组化法观察肺组织内ｉＮＯＳ定位及表达情况。结果哮喘组ＢＡＬＦ中白细胞总数（１０６４±０７５）×１０７／Ｌ、ＥＯＳ％（１２５５％±７６４％）、总蛋白含量（０１２４±００８０ｇ／Ｌ）和ＮＯ水平（５００±１．８７μｍｏｌ／Ｌ）与正常对照组比较，差异有显著性（Ｐ＜０．００１），各指标数值分别为［（３１５±０９２）×１０７／Ｌ，００２％±００４％，０００８±０００４ｇ／Ｌ，１３０±０６７μｍｏｌ／Ｌ］；肺内支气管上皮细胞ｉＮＯＳ表达增加；给予糖皮质激素后ＢＡＬＦ中白细胞总数、ＥＯＳ％总蛋白含量指标Ｃ１：（５?

Objective To investigate the role of glucocorticosteroid and theophylline in treatment of asthmatic inflammation and their effects in production of nitric oxide (NO)and the expression of inducible nitric oxide synthase (iNOS).Method A murine model was set up (A group: asthma model, N group: control mice), then the number of WBC, eosinophils%(EOS), total protein level and the NO level in brochoalveolar lavage fluid(BALF) were measured after treatment with glucocorticosteroid (C 1 group: dexamethason inhalation; C 2 group: dexamethason peritoneal injection and C 3 group: budisonide inhalation) and aminophylline(T group). The expression of iNOS was studied by histochemistry and immunohistochemistry.Result There was a significant increase in number of WBC [(10 64±0.75)×10 7/L vs (3.15±0.92)×10 7/L, P <0.001),EOS% (12 55%±7 64% vs 0.02%± 0.04%, P <0.001),total protein level (0 124±0.080 g/L vs 0.008±0.004 g/L, P <0.001) and concentration of NO (5 00±1.87 μmol/L vs 1.30±0.67 μmol/L, P <0.001) in BALF after antigen challenge, and the expression of iNOS was increased in airway epithelial cells and alveolar macrophages. After administration of steroids and theophylline, the number of WBC[C 1:(5 05±1 14)×10 7/L,C 2:(5 47±0 59)×10 7/L,C 3:(6 53±0 47)×10 7/L,T:(3 65%±1 04)×10 7/L, P <0.001],EOS%(C 1:0.10%±0 06%,C 2: 0.10%± 0.08%, C 3:0.24%±0 33%,T:2 84%±1 90%, P <0.001～ 0.005), total protein level (C 1: 0.016± 0.011 g/L, C 2: 0 010± 0.008 g/L, C 3: 0.020±0.012 g/L, T:0.012±0.008 g/L, P <0.001～ 0.05) were significantly decreased. There was a significant reduction of NO level (C 1:1.20±0.97 μmol/L, P <0.001) and iNOS expression after treated with steroids, but no significant change after management with theophylline. Conclusion EOS is main inflammatary cell in asthma. NO may play an important role in aggravating asthma. Steroids and theophylline both can inhibit cell infiltration and serum protein leakage in asthma.Steroids can also inhibit the production of NO and iNOS expression. But theophylline has no significant effect in NO production in lung.