Abstract: Abstract: Dexamethasone was used as a positive drug to establish and validate a pathological evaluation method for a lipopolysaccharide ( LPS) induced mouse acute pneumonia model，and develop a low-priced and easy preliminary pharmacodynamic evaluation model for the inflammatory and infectious diseases． The LPS-induced mouse acute pneumonia model was developed by the nasal inhalation of LPS． The pathology classification standard was set up via HE staining based on the lung injury severity against time points． Dexamethasone was adopted as a positive drug to validate the pathological evaluation method． After inhalation of LPS，the lungs were collected at different time points for pathological evaluation． A 0 – 5 level pathological classification standard of lung injury was established． This method was used to evaluate the therapeutic effect of the positive drug dexmethasone，and proved a significant difference between the LPS control and dexmethasone-treatment group． We established the pathological evaluation method for the therapeutic effect of dexamethasone in the LPS-induced mouse acute pneumonia model． The method can be used for the preliminary screening of anti-inflammatory drugs and their pharmacodynamic studies．

Key words: dexamethasone, LPS, acute pneumonia, mouse model;pathology classification

摘要： 摘要: 目的用地塞米松作为阳性药物，对脂多糖( Lipopolysaccharides，LPS) 诱导急性肺炎小鼠模型建立的病理学 评价方案进行验证，以期获得炎症和感染性疾病廉价易行的初步药效学评价模型。方法使用鼻腔吸入法制备小 鼠LPS 诱导急性肺炎模型，利用不同时间点肺炎模型小鼠肺损伤HE 染色结果建立病理学分级标准，使用地塞米松 作为阳性治疗药物对病理学评价方法进行验证。结果对LPS 吸入后不同时间点的小鼠进行全肺取样和病理学 检测，建立了0—5 级肺组织损伤病理学分级评价标准，采用该标准对地塞米松作为阳性治疗药物的治疗效果进行 评价，与LPS 对照组相比差异显著。结论获得了针对LPS 诱导急性肺炎小鼠模型建立的病理学评价方案，该方 案以地塞米松作为阳性对照药物，可以用于抗炎药物的初步筛选和药效学研究。

关键词: 地塞米松, 脂多糖, 急性肺炎, 小鼠模型, 病理评分