中文摘要：

目的探讨小窝蛋白-1（caveolin-1，Car-1）在脂多糖（hpopolysaceharide，LPS）诱导急性肺损伤（acute lung injury，ALI）大鼠肺组织中的变化。方法复制LPS致大鼠Au模型，40只SD大鼠按随机数字表法分为生理盐水对照组（Ns5mL／ks，n=8），LPS组（5mg／kgLPS尾静脉注射，分别观察3、6、24h，n=8），甲泼尼龙组（5ms／ks早泼尼龙，LPS刺激后观察6h，n=8）。分别采用Western—blot、RT—PCR、免疫组织化学法检测不同时间点肺组织中Cav-1蛋白及mRNA表达。结果LPS组大鼠肺组织病理损伤程度重，肺组织Cav-1蛋白表达明显低于对照组，Cav-1mRNA表达也低于对照组。LPS以时间依赖方式下调Cav-1蛋白（3h组：2．452±0．179，6h组：1．863±0．175，24h组：2．734±0．247）及mRNA（3h组：1．073±0．139，6h组：0．628±0．090，24h组：1．293±0．376）表达，组间比较差异有统计学意义（F值分别为23．440、47．922，均P〈0．01）。与LPS刺激6h组相比，甲泼尼龙组肺组织病理损伤程度减轻，LPS刺激下调Cav-1蛋白（1．863±0．175vs2．644．4-0．333，P〈0．01）和mRNA（0．628±0．090vs1．527±0．092，P〈0．01）表达的效应被部分抑制。结论LPS诱导Au大鼠肺组织Car-1表达下调与ALI发病密切相关，且该效应被甲泼尼龙抑制能有效地减轻肺损伤程度。

英文摘要：

Objective To investigate the changes of caveolin - 1 （ Cav - 1 ） in the lung tissues of acute lung injury （ALI） induced by lipopolysaccharide （LPS）. Methods Forty Sprague - Dawley rats were randomly （random number） divided into five groups of 8 each, including normal saline group （NS）, LPS - induced ALI model groups （respectively for 3, 6 and 24 h ） and methylprednisolone group. Rats were challenged with LPS intravenously to establish the ALI model. The expression of Cav - 1 mRNA and protein in lung tissues were determined by Western - blot, reverse transcription polymerase chain reaction （ RT - PCR） and immunohistochemistry. Results In LPS - stimulated groups, lungs tissues displayed widespread pathology damage, the expression of Cav - 1 mRNA and protein were significantly lower than in NS group （2. 172 ±0. 309,3. 150 ±0. 376, respectively）. LPS in a time - dependent manner down - regulated the expression of Cav - 1 protein （3 h group ： 2. 452 ± 0. 179,6 h group ： 1. 863 ± 0. 175,24 h group： 2. 734 ± 0.247 ） and mRNA （3 h group： 1. 073± 0. 139,6 h group： 0. 628 ± 0. 090,24 h group ： 1. 293 ±0. 376） in lung. There were significant differences among the groups （ respectively, F = 23. 440, 47. 922, all P 〈 0.01 ）. Compared with the group of LPS stimulation for 6 h, methylprednisolone significantly inhibited the down - regulated expression of Cav - 1 protein （1.863＋0.175 vs 2.644 ±0.333, P 〈0.01） and mRNA（0. 628 ±0.090 vs 1.527 ±0.092, P〈0 01 ）, and lessened the pathology damage in lung challenged by LPS. Conclusion The down - regulated expression of Cav - 1 may play important role in the development of LPS - induced ALl. Methylprednisolone can relieve LPS - induced lung injury by effectively inhibiting the down - regulated expression of Cav - 1.