目的:观察养阴清肺方调控放射性肺炎大鼠T细胞Notch信号受体1(Notch1)及Notch信号配体1(Jagged1)表达规律的影响,探讨其对放射性肺炎防治作用的机制。方法:将40只雌雄各半的SD大鼠以随机数字表法随机分为正常组、模型组、激素组、联合用药组,直线加速器对除正常组外的3组大鼠全胸单次照射,剂量为16 Gy。照射后第1天起各组予相应的药物灌胃。照射后4周,处死大鼠,取全肺称重计算肺系数,取大鼠肺组织进行苏木素-伊红(HE)染色,马松(Masson)染色,Notch1免疫组化染色,取全血标本进行免疫磁珠分选提取T细胞及流式细胞术检测Notch1比率,用提取的T细胞进行实时荧光定量PCR(Real-time PCR),蛋白免疫印迹法(Western blot)测定Notch1,Jagged1 mRNA及蛋白表达,观察各组大鼠在放射后4周肺系数改变及Notch1,Jagged1表达的变化。结果:放射后4周,各组肺系数差异明显,正常组与联合用药组肺系数最为接近;与模型组比较,养阴清肺方联合泼尼松龙可明显降低Notch1 T细胞所占比例(P<0.05),可明显降低Notch1,Jagged1mRNA表达(P<0.05),明显下调Notch1,Jagged1相关蛋白表达(P<0.05)。结论:养阴清肺方能明显下调放射性肺炎大鼠Notch1,Jagged1表达,可能是防治放射性肺炎发生发展的机制之一。 OBJECTIVE: To observe the effect of Yangyin Qingfei Recipe on the expression of Notch signaling receptor 1 (Notch1) and Notch signaling ligand 1 (Jagged1) in rats with radiation-induced pneumonia, and to explore the mechanism of prevention and treatment of radiation pneumonitis. METHODS: Forty male and half female SD rats were randomly divided into normal group, model group, hormone group, and combination group by random number table method. The linear accelerator was applied to three groups of rats except the normal group. The dose is 16 Gy. From the first day after irradiation, each group was given the corresponding drug by gavage. Four weeks after irradiation, the rats were sacrificed and whole lungs were weighed to calculate the lung coefficient. Rat lung tissue was taken for hematoxylin-eosin (HE) staining, Masson staining, Notch1 immunohistochemical staining, and whole blood specimens were taken. Immunomagnetic beads were used to extract T cells and flow cytometry was used to detect Notch1 ratio. Real-time PCR was performed on the extracted T cells, and Notch1, Jagged1 mRNA and protein were detected by Western blot. Expression, changes in lung coefficient and changes in Notch1 and Jagged1 expression were observed in all groups of rats 4 weeks after radiation. RESULTS: At 4 weeks after radiation, there was a significant difference in lung coefficient between the groups. The lung coefficients of the normal group and the combination group were the closest to each other. Compared with the model group, Yangyinqingfei side combined with prednisolone significantly reduced the proportion of Notch1 T cells ( P<0.05) significantly decreased the expression of Notch1 and Jagged1 mRNA (P<0.05), and significantly down-regulated the expression of Notch1 and Jagged1 related proteins (P<0.05). Conclusion: Yangyin Qingfei Recipe can significantly down-regulate the expression of Notch1 and Jagged1 in rats with radiation pneumonia, which may be one of the mechanisms of prevention and treatment of radiation pneumonitis.