高-低氧全肺照射对小鼠肺纤维化的影响

Effect of irradiation in high and low oxygen on mouse lung fibrosis\

目的以小鼠肺组织中ＴＧＦβ１含量变化为指标，观测高低氧（ＨＯ＋ＬＯ）照射对肺晚期损伤的生物学效应。方法雄性Ｃ５７ＢＬ小鼠，１３Ｇｙ全肺一次照射，照射同时分别吸入空气、高氧（９５％Ｏ２＋５％ＣＯ２）或高低氧（１０％Ｏ２＋５％ＣＯ２＋８５％Ｎ２），照射后不同时间取肺组织ＨＥ染色、Ｍａｓｏｎ染色、Ｖ．Ｇ．染色观察肺纤维化形成。ＲＴＰＣＲ方法测定肺组织内ＴＧＦβ１的表达。结果照射后８个月肺组织局部灶性纤维化形成。高氧组肺纤维化面积大于空气组及ＨＯ＋ＬＯ组，两者相比，差异具有显著性；ＨＯ＋ＬＯ组纤维化面积虽略高于空气组，但差异无显著性。照射后３６小时，ＴＧＦβ１表达下降，照射后２个月，ＴＧＦβ１表达升高，至照射后８个月，略呈下降趋势，但仍高于正常对照。结论低氧的加入降低单纯高氧导致的正常组织损伤，ＨＯ＋ＬＯ照射不增加肺的晚期损伤。

Objective\ To study the effect of irradiation in high and low oxygen (HO+LO) on the development of mouse lung fibrosis. Methods C 57 BL mice were divided into three groups of irradiation:in air, HO(95%O 2+5%CO 2), and HO+LO(10%O 2+5%CO 2+85%N 2). Using the lungs of C 57 BL mice, the histological changes were observed up to 8 months after whole thorax irradiation. Expression of TGF β 1 mRNA was evaluated by RT PCR. Results The area of fibrosis was 2213 scale/lung (in air), 2310 scale /lung(in HO+LO) and 6460 scale/lung(in HO), respectively. The expression of TGF β 1 decreased at 36 hours after whole thoracic irradiation, and increased after 2 months, then showed a modest elevation after 8 months when lung fibrosis appeared. Conclusion This study suggests in that irradiation that HO+LO can reduce the lung damage due to irradiation HO. TGF β 1 may play a role in the development of chronic fibrosis.