曲酸对辐射损伤小鼠免疫系统的影响

目的：探讨曲酸对辐照后小鼠免疫系统的影响。方法将20只雄性C57小鼠随机分为正常组、模型照射组、曲酸低、高剂量组。正常组动物不做任何处理,其他3组动物在照前27 h分别单次皮下注射无菌蒸馏水、75及300 mg/kg的曲酸溶液,注射体积为0．2 ml/20 g体质量。3组动物经4 Gy 60 Coγ射线单次照射。照后第2天及第8天分两批处死小鼠,分别测定小鼠的脾淋巴细胞转化能力及脾脏和胸腺指数,并制作组织病理学切片观察其形态学变化。结果与模型照射组比较,300 mg/kg曲酸给药组小鼠的脾淋巴细胞转化能力、脾脏和胸腺指数均显著提高（P＜0．01）,而且脾脏和胸腺的组织形态学变化改善明显;与正常组比较,模型照射组小鼠的上述指标均显著受损。结论急性辐射可明显损伤小鼠的免疫系统;曲酸能够增强淋巴细胞的增殖能力,对辐照后小鼠的免疫系统有显著的保护作用。     

卡拉胶寡糖对放射损伤的防护作用

目的 探讨卡拉胶寡糖对受6．0Gy X射线照射小鼠的辐射防护作用。方法采用6MV X直线加速器一次全身照射BALB／c小鼠，3个卡拉胶寡糖组照射前连续14d和照射后继续给药7d。观察小鼠30d存活率、外周血白细胞总数、胸腺指数和脾脏指数、脾脏NK细胞活性和腹腔巨噬细胞吞噬功能。结果卡拉胶寡糖组小鼠30d存活率比照射对照组提高75％～90％；而且卡拉胶寡糖能加速小鼠外周血白细胞的恢复，明显提高胸腺指数和脾脏指数，激活脾脏NK细胞的杀伤活性，增强巨噬细胞吞噬功能。结论卡拉胶寡糖对受照射小鼠有明显的辐射防护作用。     

血小板第4因子对辐射损伤小鼠免疫功能的保护作用

目的：探讨血小板第4因子（plateletfactor4，PF4）对辐射损伤小鼠免疫系统的影响。方法：雄性BALB／c小鼠随机分为3组，第1组（单纯照射组）、第Ⅱ组（PF4保护组）、第Ⅲ组（正常对照组），第Ⅱ组在照射前26h及20h腹腔注射PF440μg／kg，全身一次性5Gy60Co—γ射线照射后瑞氏染色法计数外周血淋巴细胞百分数。胸腺、脾脏制成细胞悬液计数后，MTT比色法测定胸腺及脾细胞增殖能力。结果：第Ⅱ组小鼠外周血淋巴细胞百分数下降趋势较第1组明显减慢。胸腺、脾细胞计数，第Ⅱ组明显高于第1组。淋巴细胞增殖试验，第Ⅱ组与第1组相比，小鼠胸腺及脾细胞的增殖能力明显增强。结论：PF4对免疫系统有辐射保护作用，可明显增强辐射损伤小鼠的免疫功能。     

卡拉胶寡糖对放射损伤小鼠T细胞功能和亚型的影响

目的探讨卡拉胶寡糖对受x射线照射小鼠T细胞功能和亚型的影响。方法采用直线加速器6MV X射线一次全身照射BALB／c小鼠，卡拉胶寡糖组照射前连续14d和照射后继续给药7d。检测小鼠脾脏淋巴细胞增殖反应，胸腺细胞表达CD69变化，外周血T细胞表达IL-2、IFN-γ和TNF-α变化及CD4^ ／CD8^ 比值。结果卡拉胶寡糖能有效提高脾脏T淋巴细胞的增殖能力，胸腺T细胞表达CD69显著升高，使受照射小鼠外周血T细胞产生IL-2和IFN—γ的能力显著增强，外周血T细胞表达TNF-α的能力降低，并能显著升高外周血T细胞CD4^ ／CD8^ 比值。结论卡拉胶寡糖对放射损伤小鼠的T细胞功能和亚型有明显调节作用。     

WR—2721对受中子和γ射线照射小鼠抗突变作用

用6—巯基鸟嘌呤(6—TG)为选择培养基,于照后56天检查B6CF_1小鼠脾脏T淋巴细胞次黄嘌呤转磷酸核糖基酶(HPRT)位点的突变,以观察辐射防护药WR—2721的抗突变作用。方法:雄性小鼠用~(60)Co γ射线(剂量率46.7cGy/min)或中子(0.85MeV,γ射线约含2     

031 连续极低剂量γ射线照射对大鼠免疫系统的影响

目的：研究连续极低剂量γ射线照射（１０Gy／a）是否能改变大鼠的免疫指标。方法：３～４周龄C５７BL／６雌性小鼠，每笼０只，饲养在７am～７pm照明、１９～２１℃室内，随进食和饮水。用封在塑料袋内的硝酸钍，放在笼部进行照射，剂量率为１０cGy／a。对照小鼠饲养同室内，距照射动物２m，用铅屏相隔，以FLi量计测量本底剂量。动物照射开始后第２、４、、８、１２、１８和２４个月，取小鼠脾和胸腺，分离脾细胞和胸腺细胞，制备成浓度为１０６细胞／mL细胞悬液，测定细胞表面抗原。每个样本用流式细胞仪分析７０００个细胞，测定CD４…     

β和γ射线照射肿瘤细胞的生物效应比较

目的 比较低剂量率β射线和高剂量率γ射线照射诱发肿瘤细胞生物效应特点。方法采用^32Pβ射线和^60Coγ射线照射人宫颈癌HeLa细胞系，用台盼蓝排除法和X-gal衰老细胞染色法比较两种照射肿瘤细胞死亡方式的差异。结果 ^32Pβ射线(0．375cGy/min)和^60Coγ射线(206cGy/min)照射HeLa细胞后72h的结果表明，低剂量率β射线抑制细胞增殖为渐进性，使多数的细胞在一个或几个细胞倍增周期后死亡，以增殖性死亡为主；高剂量率γ射线对细胞的抑制作用直接、迅速，细胞坏死比例高，增殖性死亡(衰老)比例低于持续低剂量照射方式。结论 不同的辐射方式对细胞的杀伤方式不同，了解其放射生物学机理有助于临床治疗方案的选择。     

雪莲培养细胞提取物对~(60)Co γ射线照射后小鼠外周血细胞的保护作用

目的研究雪莲培养细胞提取物对被60Coγ照射小鼠外周血细胞指标的影响。方法取100只昆明种雄性小鼠,随机分成5组,除空白对照组外,其余各组给予2.5 Gy60Coγ射线全身照射处理(包括模型组和雪莲培养细胞提取物低、中、高剂量组),定时检测外周血白细胞数、淋巴细胞数、血红蛋白含量、血小板含量以及红细胞相关指标,考察雪莲培养细胞提取物对被辐射小鼠的保护作用。结果小鼠被2.5 Gy60Coγ射线照射后的外周血白细胞数,淋巴细胞数,红细胞数、血红蛋白及血小板含量均显著下降。小鼠灌服雪莲培养细胞提取物后,显著促进了这些指标的回升。结论雪莲培养细胞提取物对辐射小鼠外周血细胞相关指数的恢复具有显著的促进作用。     

多糖对X线照射肿瘤小鼠T、B淋巴细胞的影响

本文用细胞化学方法研究了腹腔注入5种多糖对X线局部照射雌、雄性肿瘤小鼠外周血T、B淋巴细胞和胸腺T细胞的影响。研究结果表明,X线局部照射的雌性肿瘤小鼠,在用药组外周血T细胞全部下降,B细胞全部增加。雄性肿瘤小鼠外周血T细胞在猪苓、酵母甘露聚糖、当归Ⅱ及蜜环菌C-D组明显下降,而B细胞在用药组全部增高。酵母甘露聚糖、当归Ⅱ、蜜环菌C-D及菊叶梅衣可使X线局部照射的雌性肿瘤小鼠胸腺T细胞明显下降,在雄性肿瘤小鼠只有前两种多糖使胸腺T细胞明显下降;而猪苓却使胸腺T细胞增加。文中还讨论了雌、雄性小鼠外周血和胸腺T细胞下降与抑瘤效应的关系。     

五鹤续断对辐射损伤小鼠保护作用的研究

目的 研究五鹤续断(WHDA)注射液对辐射损伤小鼠的保护作用.方法 将160只昆明种雌性小鼠分为正常对照组、照射组和低剂量WHDA+照射组、高剂量WHDA+照射组,观察其30 d存活率;测定辐射后6 h、3 d、6 d、9 d小鼠的外周血象;测定辐射后小鼠的胸腺、脾脏和肝脏质量;测定辐射后小鼠外周血和肝脏的超氧化物歧化酶(SOD)、谷胱甘肽(GSH)及丙二酰二醛(MDA)水平.结果 WHDA可提高辐射后小鼠的存活率,对其白细胞及血小板的数量变化有显著影响,但对其胸腺、脾脏、肝脏质量均无明显影响.WHDA还能显著提高辐射后小鼠的SOD活性,增加GSH水平,降低MDA水平.结论 WHDA对辐射损伤小鼠有明显的保护作用.     

Alleviation of gamma-radiation damage by water with reduced deuterium and 18O content]

Effects of rectified water with low content of heavy stable isotopes of hydrogen (deuterium) and oxygen (18O) on radiation damage were studied in senior males of the Balb/c mice. The animals were irradiated by 60Co in unit PX-gamma-30 at a dose of 0.50 Gy. Dose rate was equal to 0.32 cGy/min. It was shown that rectified water had a positive effect on recovery of radiation damage such as impairment of immune organs (thymus and spleen), peripheral blood and marrow cells.     

胶原蛋白肽对X射线照射小鼠免疫功能的影响

目的 了解胶原蛋白肽（CP）对X射线照射小鼠免疫功能的调节作用。方法 ICR小鼠按体重分层随机分为5组,分别为健康对照组、2 Gy、5 Gy、2 Gy+CP 600 mg·kg^-1·d^-1组（2 Gy CP）和5 Gy+CP 600 mg·kg^-1·d^-1组（5 Gy CP）。6 MV X射线单次全身照射诱导免疫抑制小鼠模型,剂量率为6 Gy/min。2 Gy CP和5 Gy CP组的小鼠连续7 d腹腔注射给予胶原蛋白肽600 mg/kg。测量小鼠体质量、胸腺和脾脏质量,计算胸腺和脾脏指数;检测刀豆蛋白A（ConA）诱导的脾脏T淋巴细胞增殖能力及脾脏T淋巴细胞分泌的白介素-2（IL-2）的水平。结果 与健康对照组相比,X射线照射小鼠的胸腺指数、脾脏指数、脾脏T 淋巴细胞增殖能力及IL-2浓度显著降低（F=76.857、181.870、63.133、8.499,P<0.05）。腹腔注射胶原蛋白肽后,与同等剂量单纯照射小鼠比较,上述指标均有所恢复。结论 腹腔注射胶原蛋白肽能够增强X射线照射小鼠的免疫功能。     

电离辐射对小鼠胸腺Th17细胞相关细胞因子的影响

目的 通过研究电离辐射对小鼠胸腺Th17细胞相关细胞因子的影响,探讨高、低剂量辐射诱导不同的免疫效应中Th17细胞功能。方法 将健康ICR小鼠按随机数字表法分为健康对照组、低剂量照射组(0.05、0.075 Gy)和高剂量照射组(0.5、1.0、2.0、4.0 Gy)探讨剂量-效应关系,用X射线深部治疗机进行不同剂量的全身照射,于照射后24 h处死。同时,探讨时间-效应关系,即分为健康对照组、低剂量照射组(0.075 Gy)和高剂量照射组(2.0 Gy),于照射后12、24、48 h处死,取胸腺组织制备成组织匀浆,ELISA法检测小鼠胸腺细胞中白介素-17a(IL-17a)与白介素-21(IL-21)的浓度。结果 在时间-效应结果中,与健康对照组相比,0.075 Gy照射组胸腺细胞IL-17a和IL-21分泌量呈下降趋势,其分泌量于48 h降到最低(t=3.85、4.73,P<0.05);而2.0 Gy照射组均呈大幅度上升趋势,其分泌量在48 h达到最高(t=-6.74、-6.19,P<0.05);在剂量-效应结果中,与健康对照组相比,较低剂量照射组胸腺细胞IL-17a与IL-21分泌量下降,在0.05 Gy最低(t=8.39、16.45,P<0.05);较高剂量照射组胸腺细胞的分泌量上升,在4.0 Gy时升至最高(t=-15.60、-18.62,P<0.05)。结论 高剂量辐射可以诱导小鼠胸腺细胞IL-17a与IL-21分泌量的增加,而低剂量辐射使其下降,表明Th17细胞相关的细胞因子在低剂量辐射诱导的免疫功能增强效应和高剂量辐射诱导免疫抑制效应中起着重要的作用。     

Alterations of immune functions induced by 12C6+ ion irradiation in mice

PURPOSE: To estimate the biological risks to the immune system of the type of space radiation, 12C6+, encountered by cosmonauts during long-term travel in space. MATERIALS AND METHODS: The Kun-Ming strain mice were whole-body irradiated by 12C6+ ion with 0, 0.01, 0.05, 0.075, 0.2, 0.3, 0.5, 0.75, 1 or 2 Gy, at a dose rate of 1 Gy/min. At 35 days after irradiation, the thymus and spleen weights were measured, the natural killer (NK) cells activity of spleen was determined by 3-(4, 5-dimethylthiazol-2-yl)- 2, 5-diphenyl tetrazolium bromide (MTT), and the interferon-gamma (IFN-gamma) levels in serum and thymus were detected with enzyme-linked immunosorbent assays (ELISA). RESULTS: The results showed that the thymus weight, IFN-gamma levels in serum and the activity of splenic NK-cells had significantly increased at a dose of 0.05 Gy. With further dose increase, the weight of spleen continued to increase but the weight of thymus, IFN-gamma level and NK-cells activity declined. CONCLUSIONS: These results suggest that the dose of 0.05 Gy irradiation has a stimulatory effect on mouse immunity; this effect declined with increasing dose.     

血管内皮生长因子转基因治疗小鼠辐射损伤的实验研究

目的 通过构建血管内皮生长因子(VEGF)基因的真核表达质粒,并将其转入受照小鼠机体,研究VEGF蛋白表达对放射损伤的救治作用及其分子机制。方法 昆明种小鼠通过随机化分组表法随机分为正常对照组、单纯照射组和转基因组。转基因组应用VEGF重组质粒进行肌肉注射,注射后24 h接受8 Gy X射线照射,进行小鼠临床表现和死亡率观察。并于照后不同时间处死动物,进行组织器官病理学和原位胸腺和脾细胞凋亡检测。结果 用PCR方法从pSP73/H_VEGF165质粒扩增得到VEGF₁₆₅基因片段,经双酶切后与酶切的pcDNA3.1载体连接,构建重组质粒pcDNA3.1/ VEGF₁₆₅,经电泳和测序表明序列与GeneBank完全一致。X射线8 Gy照射小鼠,单纯照射组14 d内死亡率为64%,而转基因组为36%,两组比较差异有统计学意义(t=3.92,P＜0.05)。转基因组小鼠胸腺和脾组织的细胞凋亡率显著降低(t=3.11、3.53,P＜0.05),放射病理损伤明显改善。结论 成功构建了重组质粒pcDNA3.1/ VEGF₁₆₅,重组质粒转基因治疗可显著降低严重辐射损伤小鼠的死亡率,显著减低胸腺和脾脏细胞凋亡率,明显改善免疫器官的病理变化。     

维生素D对不同剂量X射线照射小鼠免疫功能的保护作用

目的 观察维生素D对不同剂量X射线照射小鼠免疫功能的影响。方法 将小鼠采用随机数字表法分为5组:健康对照组、2 Gy和5 Gy照射组、2 Gy+药物(维生素D)组和5 Gy+药物(维生素D)组。给药组小鼠在不同剂量X射线照射后,连续7 d腹腔注射6 IU维生素D[1,25(OH)₂D₃]/g体重,于给药后第8天,5组小鼠均处死。测定小鼠体重、胸腺和脾脏指数,ConA诱导的脾脏T淋巴细胞增殖能力,ELISA法检测脾细胞IL-2的分泌量。结果 与健康对照组相比,2和5 Gy照射组小鼠脾脏T淋巴细胞增殖能力、脾细胞IL-2的分泌量均显著降低(F=36.20、7.13,P<0.05);与2 Gy照射组相比,2 Gy+药物组小鼠胸腺指数、脾脏指数、脾脏T淋巴细胞增殖能力均显著增高(t=-2.54、-2.24、-2.84,P<0.05);与5 Gy照射组相比,5 Gy+药物组小鼠的胸腺指数、脾细胞IL-2的分泌量显著增高(t=-5.02、-2.64,P<0.05)。结论 维生素D能够改善受照小鼠的免疫功能,但随照射剂量增大,改善作用减弱。     

西咪替丁对胸部分割照射小鼠脾脏损伤的治疗作用

目的探究西咪替丁(CMTD)对局部分割照射小鼠的治疗作用。方法雄性C57BL/6小鼠30只,随机单位组设计分为对照组、单纯照射组和照射给药组(CMTD,100 mg/kg),每组10只;采用X射线局部分割照射小鼠右胸腔,8 Gy/d照射,连续3 d,累积照射剂量为24 Gy,剂量率为0.883 Gy/min。照射后连续7 d给予照射给药组小鼠灌胃CMTD(100 mg·kg^-1·d^-1),对照组和单纯照射组给予生理盐水。照射后第7天检测小鼠体重、脏器指数、脾脏T淋巴细胞亚群、B淋巴细胞亚群、NK细胞亚群变化以及脾脏组织病理学改变。结果分割照射对小鼠体重影响不大,但可诱发远端效应,使脾脏脏器指数降低为(0.369±0.011),与对照组的(0.396±0.022)比较,差异有统计学意义(t=2.978,P<0.05);改变脾脏病理结构,脾脏CD3+、CD4+、CD8+、CD3+CD4+、CD3+CD8+淋巴细胞比例显著降低(t=5.754、3.570、4.442、5.281、4.570,P<0.05)。而照射给药组小鼠体重恢复明显,脾脏组织损伤缓解,脾脏淋巴细胞亚群比例恢复,CD3+、CD3+CD4+、CD3+CD8+淋巴细胞显著升高(t=3.523、2.706、2.520,P<0.05),但仍低于正常水平。结论CMTD可有效改善X射线分割照射对小鼠脾脏的损伤,提高照后小鼠的免疫功能,可作为潜在的抗辐射治疗药物。     

EPR study of mouse tissues in search for adaptive responses to low level whole-body X-irradiation.

Effect of a low dose of whole-body X-irradiation (D1 = 0.075 Gy) of mice on some biochemical changes induced in the spleen and thymus by a subsequent challenge dose (D2 = 1.5 Gy) was studied by electron paramagnetic resonance (EPR). Kunming and SHK mice were used. Concentration of ribonucleotide reductase (RR) in the spleen and thymus of unirradiated Kunming mice was 0.70 and 0.46 microM respectively, and of unirradiated SKH mice--0.37 and 0.21 microM respectively (systematic error 45%). For mice exposed only to the low dose (D1 group), a stimulating effect on RR activity in spleen and thymus was found, while in mice subjected only to the D2 dose (D2 group) activity of the enzyme in the organs decreased considerably 18 h after irradiation. The group of mice irradiated with D1 and D2 doses, given at a 6-h interval (D1 plus D2 group), showed a RR activity in the organs lower than D1 and higher than D2 groups. This finding indicates that there exists an adaptation-like response to a low-dose whole-body irradiation in murine spleen and thymus. This low 'inductive' dose makes the organs' RR less susceptible to inhibition induced by a subsequent challenge dose. Preliminary results showed that the same kind of response is probably a characteristic of the RR content of splenocytes as well as of the rate of thymidine incorporation into splenocytes. 5-Thyml radicals of DNA (TH radicals) induced in whole tissues by gamma-irradiation in vitro at 77 K were also studied. Radiochemical yield of these radicals (4.0 and 5.3 nmol j-1), for spleen and thymus respectively of unirradiated Kunming mice, and 2.3 and 2.6 nmol J-1, for spleen and thymus respectively of unirradiated SHK mice (systematic error 30%), decreased significantly in both organs upon D2 irradiation. This decrease, however, was the consequence of DNA content diminishing upon D2 irradiation rather than change of DNA radiosensitivity: the beta value of TH radicals, i.e. yield of radicals per unit mass of DNA in each organ was equal for the mice from all D1, D1 plus D2, D2 and control groups. The beta values of TH radicals in mouse spleen and thymus were of the same order of magnitude compared with the yield of the single-strand breaks of DNA measured previously in rat organs just after whole-body irradiation, i.e. about 1 x 10(2) (Gy x 10(12) Da)-1.     

Alterations of immune functions induced by 12C6+ ion irradiation in mice

Purpose:?To estimate the biological risks to the immune system of the type of space radiation, 12C6+, encountered by cosmonauts during long-term travel in space.

Materials and methods:?The Kun-Ming strain mice were whole-body irradiated by 12C6+ ion with 0, 0.01, 0.05, 0.075, 0.2, 0.3, 0.5, 0.75, 1 or 2 Gy, at a dose rate of 1 Gy/min. At 35 days after irradiation, the thymus and spleen weights were measured, the natural killer (NK) cells activity of spleen was determined by 3-(4, 5-dimethylthiazol-2-yl)- 2, 5-diphenyl tetrazolium bromide (MTT), and the interferon-γ (IFN-γ) levels in serum and thymus were detected with enzyme-linked immunosorbent assays (ELISA).

Results:?The results showed that the thymus weight, IFN-γ levels in serum and the activity of splenic NK-cells had significantly increased at a dose of 0.05 Gy. With further dose increase, the weight of spleen continued to increase but the weight of thymus, IFN-γ level and NK-cells activity declined.

Conclusions:?These results suggest that the dose of 0.05 Gy irradiation has a stimulatory effect on mouse immunity; this effect declined with increasing dose.     

低水平电离辐射单次或分割照射法的抗肿瘤效应比较

目的比较低水平电离辐射(LLIR)单次与分割照射的抗肿瘤效应。方法选用C57BL/6和ICR品系小鼠分别移植Lewis肺癌和S180肉瘤细胞,24h后再分别接受7.5cGy单次照射和分割照射(1.5cGy×5d);然后观察20d抑瘤率、脾NK细胞活性、T淋巴细胞表面CD4、CD8水平的变化以及荷瘤鼠的平均寿命。结果单次与分割照射对Lewis肺癌的抑瘤率分别为40.34%和51.19%,对S180肉瘤为34.26%和30.98%;脾NK细胞活性照后1～4d升高;CD4、CD8水平及CD4/CD8比值均有不同程度增高;荷瘤鼠的生命延长率分别为8.45%和8.84%。结论本实验采用的低水平单次或分割照射对Lewis肺癌和S180肉瘤均有明显的抑瘤效果,能显著增强荷瘤机体的免疫机能以及延长荷瘤鼠的平均寿命。经比较,两种照射方式在肿瘤生长抑制和免疫刺激作用等方面差异无显著性(P＞0.05)。