【摘要】 目的阐明当归对放射性肺损伤过程中TNFα水平的动态影响,寻求预防或治疗放射性肺损伤的有效途径。方法成年雌性C57BL/6小鼠72只,随机分为4个组⑴空白对照组(9只)腹腔注射生理盐水20ml/(kg·d);⑵单纯当归组(9只)腹腔注射25%当归注射液20ml/(kg·d);⑶单纯照射组(27只)全肺单次照射12Gy+腹腔注射生理盐水20ml/(kg·d);⑷照射+当归组(27只)全肺单次照射12Gy+腹腔注射25%当归注射液20ml/(kg·d)。生理盐水和25%当归注射液于照前1周开始注射,直至照射后2周结束。左肺做组织学与免疫组化分析,右肺做总RNA提取及实时定量RTPCR分析。结果空白对照组和单纯当归组免疫组化阳性细胞数相对较低,仅波动在8～17个之间。单纯照射组阳性细胞数较上述两组明显增高(P<0.01),尤以1周后为甚。照射+当归组阳性细胞数则介于两者之间,但仍然显著低于单纯照射组(P<0.01)。单纯照射组TNFαmRNA相对含量与单纯当归组和空白对照组差异均有统计学意义(P<0.01)。照射+当归组TNFαmRNA相对含量较单纯照射组差异无统计学意义(P=0.078),可能与样本数较少有关。结论TNFα在放射性肺损伤发生、发展过程中起重要作用,当归能明显降低该过程中TNFα表达水平,其可能通过调控该细胞因子起辐射防护作用。更多还原

【Abstract】 Objective To investigate the ability of Angelica Sinensis to affect the radiation-induced tumor necrosis factor α(TNF-α) release in the animal model, so as to find an effective method in reducing the lung toxicity after thoracic irradiation. Methods The chest of 72 C57BL/6 mice were exposed to either sham irradiation or single fraction of 12 ?Gy after having been randomized into 4 groups:1. 9 mice received neither irradiation nor Angelica Sinensis but received i.p injection of NS 20?ml/(kg·d)(NT group);2. 9 mice received Angelica Sinensis only but no irradiation though receiving i.p,NS(AS group);3. 27 mice received whole lung 12 ?Gy irradiation and i.p,NS without Angelica Sinensis (XRT group) and 4. 27 mice received both i.p,25% Angelica Sinensis 20?ml/(kg·d) and whole lung 12?Gy irradiation(AS/XRT group). The TNF-α mRNA expression in the lung tissue were quantified by ’real-time’ quantitative reverse transcriptase polymerase chain reaction (RT-PCR). Immunohistochemical detection method (Streptavidin-Peroxidase method) and positive cell counting were used for objective quantification of TNF-α protein expression. Results NT and AS group exhibited low level of TNF-α protein expression with positive cell counts between 8 and 17. And there was an significantly elevated level of TNF-α positive inflammatory cells in XRT group(P<0.01). The number of the positive cells in AS/XRT group was between NT and AS group and XRT group with the difference between AS/XRT group and XRT group significant(P<0.01). The results of ’real-time’ quantitative RT-PCR showed that the relative mRNA expression of cytokine TNF-α in XRT group was significantly higher than the nonirradiated groups(P<0.01).The lung tissue of the mice which were treated by Angelica Sinensis revealed only a minor radiation-mediated TNF-α response on mRNA level, but the statistical comparison of the TNF-a mRNA expressions between the XRT and AS/XRT groups was not significant(P=0.078),which was possibly due to the data variability and the relatively limited number of specimens available. Conclusions A significant radiation-induced increase of TNF-α in the lung tissue and the predominant localization of TNF-α in area of inflammatory cell infiltration suggests the involvement of cytokine in the pathogenesis of radiation-induced lung injury.更多还原