微波辐射后大鼠肺组织中VEGF和AQP5的表达变化

The express changes of VEGF and AQP5 of rat lung after microwave radiation

目的探讨微波辐射后大鼠肺组织中VEGF和AQP5的表达及其意义。方法采用10、30和100 mW/cm2的微波辐射96只二级Wistar雄性大鼠,于辐射后6 h、1 d、3 d、7 d和14 d取肺组织,采用免疫组织化学和图象分析技术探讨血管内皮生长因子(vascular endothelial growth factor,VEGF)和水通道蛋白5(aquaporin5,AQP5)在辐射后大鼠血-气屏障(blood-air barrier)改变中的作用。结果(1)大鼠肺组织中VEGF表达变化:假辐射组VEGF见于血管内皮细胞浆,呈弱阳性表达。30、100 mW/cm2组微波辐射后6 h^7 d,VEGF于血管内皮细胞浆呈阳性表达,6 h即见增加,1 d达高峰,3、7 d也呈阳性表达,14 d恢复至正常。图象分析结果显示,6 h^7 d与假辐射组相比有显著性差异(p<0.05或p<0.01),且上述改变与辐射剂量呈正相关;(2)大鼠肺组织中AQP5表达改变:AQP5在假辐射组Ⅰ型肺泡上皮细胞膜呈阳性分布,上述三组在辐射后Ⅰ型肺泡上皮细胞膜AQP5的表达均减弱,其中100 mW/cm2组减弱最明显,1 d呈弱阳性,3 d见恢复,7 d基本恢复至正常。结论10~100 mW/cm2的微波辐射可使VEGF表达增加,AQP5表达减少,并且有时效性和量效性关系,二者可能参与了微波辐射致血-气屏障损伤的病理生理过程。

Objective To investigate VEGF（vascular endothelial growth factor） and AQP5 （aquaporin5） changes of rat lung after microwave radiation. Methods 96 rats were exposed to microwave which average power densities were 10, 30 and 100 mW/cm^2 respectively and killed on 6 h, 1 d, 3 d, 7 d and 14 d after radiation, Apply immunohistochemistry and image analysis to approach the effect of VEGF and AQP5 of rat blood-air barrier after microwave radiation, Results （1） The change of VEGF in rat lung： In sham-radiation group VEGF weakly positive appeared in kytoplasm of vascular endothelial cell, After 30, 100 mW/cm^2 microwave radiation, 6 h -7 d VEGF expressed positive in kytoplasm of vascular endothelial cell, At 6 h VEGF were increased more in radiation group than in sham-radiation group and expressed most positive on 1 d and on 3 d, 7 d were also expressed positive and recovered on 14 d. Image analysis showed that on 6 h - 7 d the VEGF had significant difference （ P 〈 0. 05 or P 〈 0.01 ） and had direct correlation with quantity of radiation, （2） The change of AQP5 in rat lung： In sham-radiation group AQP5 positive appeared on the cellular membrane of type I alveolar epithelial cell. AQP5 were decreased after microwave radiation in 10, 30 and 100 mW/cm^2 groups. In 100 mW/cm^2 group, AQP5 were weakly positive on 1 d, gradually recovered after 3 d, turned mainly normal at 7 d. Conclusion 10 - 100 mW/cm^2 microwave radiation can change VEGF and AQP5 quantity of rat blood-air barrier and these changes had positive correlation with radiation quantity. VEGF and AQP5 possible participated the pathological physiological impaired process of microwave radiation on rat blood-air barrier.