一氧化氮在哮喘大鼠气道炎症中的作用

The Role of Nitric Oxide in Airway Inflammation of Asthmatic Rat

为探讨一氧化氮在哮喘大鼠气道炎症中的作用，采用卵白蛋白作为致敏原制备哮喘大鼠模型，用Ｓ—Ｐ免疫组化染色方法对肺组织诱导型一氧化氮合酶ｉＮＯＳ的活性测定及定位分析。结果显示：哮喘大鼠肺组织（ｉＮＯＳ）的表达活性明显高于正常对照组（Ｐ＜０００１）。主要存在于支气管上皮细胞，支气管平滑肌细胞，肺泡上皮，血管内皮和平滑肌细胞，浸润的中性粒细胞和巨噬细胞，而淋巴细胞表达不明显。用甲基强的松龙处理后哮喘大鼠肺组织诱导型一氧化氮合酶表达明显降低。说明一氧化氮在哮喘气道炎症中起重要作用，甲基强的松龙治疗哮喘可以减轻气道炎症。

In order to study the role of nitric oxide (NO) during the airway inflammation of asthmatic rat,the expression of inducible nitric oxide synthase (iNOS) in the lung tissue of asthmatic rats was investigated.Used ovalbumin as a sensitizer,we established an asthmatic animal model.Activities of iNOS were measured by using S-P immunohistochemical method.The results showed that in asthmatic rat group,lung tissue had stronger immunostaining for iNOS than control group( P <0 001),it was main present in the bronchial epithelial,alveolar epithelial,bronchial smooth muscle,vascular endothelial and smooth muscle cells and inflammatory cells such as macrophage and neutrophil.In glucocorticoid group,there was down regulatron of iNOS immunoreactivity,as compared with asthmatic rat group.The increased expression of iNOS in asthmatic rat lung tissue suggest NO plays a critical role in asthmatic inflammation,and glucocorticoid could inhibit the expression of iNOS.