加味麻杏石甘汤对急性放射性肺炎大鼠Smad蛋白表达的干预作用

Intervention of Modified Maxing Shigan Decoction on Smad Protein Expression in Rats with Acute Radiation Pneumonitis

目的明确加味麻杏石甘汤对大鼠急性放射性肺炎的干预作用,探讨其作用机制。方法复制急性放射性肺炎SD大鼠模型,按高、中、低剂量组分别给予加味麻杏石甘汤灌胃,阴性对照组、模型组予生理盐水灌胃,2m L/(220g·d),连续8周。各组分别于第2、4、8周随机处死4只大鼠,取肺组织,采用Western Blot方法检测大鼠肺组织P-Smad2、P-Smad3、Smad6、Smad7蛋白表达情况。结果经照射后,模型组P-Smad2、P-Smad3表达上调(P均<0.01),各用药组较模型组有不同程度下降(P均<0.01);模型组Smad6、Smad7表达下调(P<0.01),各用药组较模型组有不同程度上升(P<0.05,P<0.01)。结论加味麻杏石甘汤能下调急性放射性肺炎模型大鼠肺组织P-Smad2、PSmad3蛋白表达,上调Smad6、Smad7蛋白表达。

Objective To investigate the effect of modified Maxing Shigan decoction on rats with acute radiation pneumonitis and the underlying mechanism. Methods SD rat models of acute radiation pneumonitis were established. Rats were divided into modified Maxing Shigan decoction groups（high dose, middle dose, low dose）, control group, and model group. Modified Maxing Shigan decoction groups were intragastrically given 3, 1.5, and 0.75g/m L（2m L/220g·d） of the corresponding drug for 8 weeks. Model group and control group were given equivalent volume of normal saline for the same period of time. Every 4 rats in each group were randomly sacrificed at 2, 4, and 8weeks to obtain lung tissue. The expressions of P-Smad2, P-Smad3, Smad6, and Smad7 proteins in lung tissue were analyzed by Western-blotting. Results After radiation, the expressions of P-Smad2 and P-Smad3 proteins in model group were up-regulated（P〈0.01）, while those in modified Maxing Shigan decoction groups were all downregulated（P〈0.01）. The expressions of Smad6 and Smad7 proteins in model group were down-regulated（P〈0.01）,while those in modified Maxing Shigan decoction groups were up-regulated（P〈0.05 or P〈0.01）. Conclusion Modified Maxing Shigan decoction can down-regulated the expressions of P-Smad2 and P-Smad3 proteins and up-regulated the expression of Smad6 and Smad7 proteins in lung tissue of rats with acute radiation pneumonitis.