肺TGF-β_1水平及血流分布变化与放射性肺损伤的关系

The level of TGF-β_1 in alveolar lavement liquid, the change of pulmonary blood flow distribution and the radiation-induced pulmonary damage

目的观察放射性肺损伤过程中肺血流分布改变和肺泡灌洗液及血清中TGF-β1水平变化.方法将纯种新西兰白兔55只分为对照组、20和30 Gy照射组（照射组再各分5个亚组）,5只/组.照射后不同时间进行肺灌注扫描观察肺血流分布及使用酶联免疫吸附分析法检测肺泡灌洗液和血清中TGF-β1水平,并观察照射后肺组织病理形态学改变.结果照射后左肺血流量占全肺血流量百分率不断下降,肺泡灌洗液和血清中TGF-β1水平逐渐升高,以3～6个月最显著.与放射性肺损伤病理形态学变化趋势相一致.结论肺泡灌洗液及血清中TGF-β1水平可预测放射性肺损伤发展趋势,肺血流量分布变化可间接反映放射性肺损伤病理形态学改变程度.

Objective To investigate the changes of pulmonary blood flow distribution and the levels of TGF-β1 in alveolar lavement liquid and the sera in the course of radiation-induced pulmonary damage. Methods Fifty-five pure-blooded New Zealand rabbits were randomly divided into the control group, and 20 Gy and 30 Gy irradiated groups （left lung exposed to 6 MV X-ray generated by linear accelerator, 2 Gy/min）. The pulmonary blood flow distribution was observed with lung perfusion scanning. The levels of TGF-β1 in the alveolar lavement liquid and the sera in different time since irradiation were measured with ELISA. The pathomorphological changes were evaluated. Results The percentage of blood stream （left lung vs. the whole lungs） decreased; the levels of TGF-β1 in the alveolar lavement liquid and the sera increased with the irradiation especially for the period of 3-6 months after the irradiation, and these changes reflected the pathomorphological alterations in the radiation-induced pulmonary damage. Conclusions The levels TGF-β1 in the alveolar lavement liquid and sera predicted the development and prognosis of radiation-induced pulmonary damage. The change of distribution of pulmonary blood flow indirectly reflected the pathomorphological changes of radiationinduced pulmonary damage.