凉血活血中药对剂量分割重复照射下大鼠肺组织TNF-α和bFGF的影响

Modulation by Blood-cooling and Blood Flow-promoting Herbs to the expression of TNF-α and bFGF in radiation induced lung damage of rats

目的 通过观察凉血活血中药对剂量分割重复照射下大鼠肺组织肿瘤坏死因子-α（TNF-α）、碱性成纤维生长因子（bFGF）在不同时相动态表达的影响，探讨其防治放射性肺损伤的作用机制。方法160只Wistar种雌性大鼠随机分为单纯照射组（40只）、中药治疗组（40只）、单纯中药组（40只）和空白对照组（40只）。用直线加速器对单纯照射组和中药治疗组大鼠右肺进行分次照射（3Gy／次，2次／周，累积剂量最高为30Gy），于照射开始后第3、5、8、12和26周5个时间点分别处死各组各8只大鼠，取材切片行HE和免疫组化染色，观察大鼠肺组织病理改变和不同时相TNF-α和bFGF的表达。结果单纯照射组大鼠肺组织于照射第5周急性放射性肺炎最重，第26周肺纤维化明显，不同时相TNF-α和bFGF表达明显增强（P〈0．01）；中药治疗组大鼠各时相TNF-α、bFGF的表达均组明显低于单纯照射组（P〈0．01）。结论在剂量分割重复照射过程中，应用凉血活血中药可抑制致炎因子和致纤维化因子的表达，减轻早期放射性肺炎的炎症反应和后期放射性肺纤维化的程度，因而对放射性肺损伤具有防治作用。

Objective To observe the modulation by Blood-cooling and Blood Flow-promoting Herbs to expressions of tumor necrosis factor u （TNF-α） and basic fibroblast growth factors （bFGF） in radiation-induced lung injury of rats at different radiation times, and explore the mechanism of prevention and curative effect of the herbs on radsation lurg injury. Methods 160 wistar rats were randomly allocated into irradiation group, treatment group, herb- fracture group and control group. The first two groups were irradiated to right hemithorax with a dose of 30 Gy/10 fraction/5 weeks. Animals were sacrificed at weeks 3,5,8,12 and 26 post irradiation the level of immunoreactivity of cytokine TNF-u and bFGF was evaluated. Results The acute radiation-induced pneumonia ocurred at weeks 3 and was most serious at weeks 5 and pulmonary fibrosis was remarkable at the late phase in irradiation group. The pneumonia and fibrosis of treatment group were lighter than that of irradiation group. Expressions of TNF-α and bFGF reached their peaks at weeks 5 and 26 of respectively. The expressions in treatment group was significantly lower than that the irradiation group（ P 〈 0.01）. Conclusions Blood-cooling and Blood Flow-promoting Herbs can prevent and treat the radiation-reduced lung injury by restraining the expression of TNF-α and bFGF.