厄洛替尼在小鼠急性肺损伤中作用及对肺表面活性物质相关蛋白A表达的影响

The role of erlotinib in the acute lung injury and the expression of surfactant protein A

目的探讨厄洛替尼在脂多糖（lipopolysaccharide，LPS）诱导的小鼠急性肺损伤（acute lung injury，ALI）中的作用及对肺表面活性物质相关蛋白A（surfactant protein A，SP．A）表达的影响。方法C57BL／6小鼠随机（随机数字法）分为对照组（Control组），100mg／kg的厄洛替尼灌胃组（ER组），2mg／kgLPS诱导的ALI组（LPS组），100mg／kg的厄洛替尼灌胃1h后再用2mg／kgLPS处理的药物组（ER＋LPS组），24h后收集肺组织及肺泡灌洗液。HE染色法观察肺组织病理学改变并进行肺组织病理损伤评分，肺湿／干质量比值、肺泡灌洗液总蛋白浓度及细胞计数测定肺水肿程度，免疫组织化学染色及Western Blot法检测肺组织中SP—A的表达。各组间采用单因素方差分析，组间两两比较采用LSD-t检验。结果HE染色见与Control组相比较，ER组未见明显肺损伤，LPS组可见明显的肺损伤，ER＋LPS组肺损伤程度减轻；肺病理损伤评分显示LPS组评分（0．846±0．047）明显高于Control组（0．056±0．008）及ER组（0．064±0．037），而ER＋LPS组（0．279±0．020）则明显低于LPS组，差异具有统计学意义（P〈0．05）。肺湿／干质量比值、肺泡灌洗液总蛋白浓度及细胞计数结果显示，LPS刺激后肺水肿程度明显增加，ER处理能减轻肺水肿程度（P〈0．05）。Western Blot及免疫组织化学结果显示SP-A的表达在LPS组明显偏低，而ER处理后其表达则升高（P〈0．05）。结论厄洛替尼能够保护LPS诱导的肺损伤，并且可能与其调节SP—A的表达相关。

Objective To investigate the role of erlotinib in the expression of surfactant protein A （SP-A） in LPS-induced acute lung injury （ALI） of mice model. Methods C57BL/6 mice were randomly （random number）divided into control group （n=6）, ER group （n=6）, LPS group （n=6）, and ER＋LPS group （n=6）. In the LPS group, 2 mg/kg LPS was instilled into trachea of mice to induce lung injury. In control group, normal saline was instilled into trachea of mice instead. In the ER＋LPS group and ER group, 100 mg/kg of erlotinib was instilled into stomach of mice, and one hour later. 2 mg/kg LPS was instilled into trachea of mice in ER＋PLS group to induce lung injury. Twenty-four hours later, bronchoalveolar lavage fluid （BALF） and lung tissue of mice in four groups were collected. HE staining were used for evaluating pathological changes of lung injury. Lung wet/dry weight ratio, protein concentrations and total cell numbers in the BALF were measured to determine the degree of pulmonary edema. Immunohistochemical staining and Western Blot were used for testing the protein expression of SP-A, Data of multiple groups were analyzed by one way variance （ANOVA） and inter-group comparisons were made by the least significant difference （LSD） tests. Results There was no significant difference in lung injury score （LIS） between control group （0.056±0.008） and ER （0.064±0.037） group, The LIS in LPS group （0.846±0.047） was higher than that in control group, however the LIS in ER＋LPS group （0.279±0.020） was significant lower than that in LPS group （P 〈 0.05）. Lung wet/dry weight, SP-A concentration and total cell numbers in the bronchoalveolar lavage fluid revealed that the degree of pulmonary edema in LPS group was higher than that in control group, and this pulmonary edema was reversed by erlotinib treatment. Immunohistochemical staining and Western blot showed that the expression of SP-A in LPS group was decreased compared with control group, but it was recovered after erlotinib treatment （P 〈 0.05）. Conclusions Erlotinib could protect the LPS-induced ALI, and it may be related to the regulation of SP-A,