Abstract: Background　Thymus is the most important central immune organ，which is vulnerable to radiation damage resulting in immune damage.At present，there are still some defects in thymus protective agents developed at home and abroad：Traditional Chinese Medicine has attracted more and more attention because of its high efficiency and low toxicity.Objective　To study the protective effect of Bushen Jiedu prescription on radiation-induced thymus injury in mice.Methods　A total of 90 mice were randomly divided into blank group（BG），radiation group（RG），radiation+amifostine group（AG），radiation+Bushen Jiedu prescription prevention and treatment group（BPT），radiation+Bushen Jiedu prescription prevention group （BP），with 18 mice in each group in January 2019.After 3 days of adaptive feeding，BPT group and BP group were intragastrically administered with Bushen Jiedu prescription（0.25 ml/rat） and RG group，AG group were intragastrically administered with the same amount of 0.9% sodium chloride solution for 10 days.On the 11th day after the experiment，all mice except those in BG group received one-time 4 Gy 60Co gamma-ray radiation at the same distance，and AG group was injected 200 mg/kg of amifostine into the left abdominal cavity 30 minutes before irradiation.After irradiation，BPT group continued to be intragastrically administered with Bushen Jiedu prescription，while the remaining four groups were given 0.9% sodium chloride solution at the same dose.The general condition of mice was observed.At the 1st，7th and 14th day after radiation，the thymus index was calculated and histological structure of thymus was observed under light microscope on the 7th day after irradiation.Results　After irradiation，the general situation of five groups of mice was worse than that before irradiation，with specific manifestations of decreased activity，poor mental state，and decreased gloss of fur，especially RG group，with five mice had hair mass exfoliation.On the 1st，7th and 14th day after irradiation，thymus index of BG group was higher than that of the other four groups（P<0.01）：on the 7th day after irradiation，thymus index of BPT and AG groups were higher than that of RG group，and that of BP group was lower than that of BPT group（P<0.01）：on the 14th day after irradiation，thymus index of BPT group was higher than that of RG，AG and BP groups（P<0.05）．The structure of thymus in BG group was complete，medulla could be seen in the cortex，and round or oval thymic corpuscles could be seen in the center.Trabecular structure in RG group was destroyed with unclear boundaries and blurred thymic corpuscles.The other three groups had the same pathological manifestations，some had destroyed trabecular lobules，dimly visible thymic corpuscles，and unclear cortical and medullary boundaries.BP group also showed more inflammatory cell infiltration.Conclusion　Bushen Jiedu prescription can reduce radiation-induced thymus tissue damage in mice and plays a good role in radiation protection.

Key words: Radiation injuries, Thymus gland, Mice, Bushen Jiedu prescription

摘要： 背景　胸腺是最重要的中枢免疫器官，在接受射线后易受损造成免疫损伤，目前国内外研制的胸腺防护剂仍存在缺陷，中药因其高效低毒的特性，越来越受到重视。目的　研究补肾解毒方对放射致小鼠胸腺损伤的防护作用。方法　2019年1月，将90只C57BL/10J小鼠采用随机数字表法分为5组：空白对照组、单纯放射组、放射+氨磷汀组、放射+补肾解毒方防治结合组和放射+补肾解毒方预防组，每组18只。适应性饲养3 d后，放射+补肾解毒方防治结合组、放射+补肾解毒方预防组每日予以补肾解毒方汤剂灌胃（0.25 ml/只），同时单纯放射组和放射+氨磷汀组予以等剂量0.9%氯化钠溶液连续灌胃10 d，第11天除空白对照组外，其余4组小鼠均接受与照射源同等距离的一次性4 Gy 60Coγ-射线全身照射，其中放射+氨磷汀组小鼠在照射前30 min于左侧腹腔内注射氨磷汀200 mg/kg。照射后，放射+补肾解毒方防治结合组继续予以补肾解毒方灌胃，余4组给予等剂量0.9%氯化钠溶液灌胃。观察小鼠一般情况，在照射后第1、7、14天进行取材，计算胸腺指数，在光镜下观察照射后第7天各组胸腺组织结构。结果　五组小鼠在照射后一般情况均较照射前差，具体表现为活跃度下降、精神状态不佳、皮毛光泽度下降，尤其单纯放射组程度更甚，其中5只小鼠出现毛发块状脱落症状。照射后第1、7、14天，空白对照组胸腺指数均高于其余4组（P<0.01）；照射后第7天，放射+氨磷汀组、放射+补肾解毒方防治结合组胸腺指数高于单纯放射组，放射+补肾解毒方预防组低于放射+补肾解毒方防治结合组（P<0.01）；照射后第14天，放射+补肾解毒方防治结合组胸腺指数高于单纯放射组、放射+氨磷汀组和放射+补肾解毒方预防组（P<0.05）。空白对照组胸腺结构完整，皮质内可见髓质，中央可见圆形或椭圆形胸腺小体；单纯放射组小梁结构破坏，界限不清，胸腺小体模糊；其余3组病理表现基本一致，部分小梁小叶结构破坏，胸腺小体隐约可见，皮质髓质界限不清，其中放射+补肾解毒方预防组还表现出更多炎性细胞浸润。结论　补肾解毒方能减轻放射所致小鼠胸腺组织损伤，发挥了良好的放射防护作用。

关键词: 辐射损伤, 胸腺, 小鼠, 补肾解毒方