【作者】 聂继华；

【导师】 童建；

【作者基本信息】 苏州大学 ， 卫生毒理学， 2006， 硕士

【摘要】 目的:从辐射防护角度研究蜂胶对⁶⁰Co-γ射线照射及氡吸入对大鼠损伤的防护作用。方法:（1）⁶⁰Co-γ射线照射实验:雄性Wistar大鼠18只,随机分为3组:辐射组﹑蜂胶预防组及蜂胶治疗组,每组6只。蜂胶预防组于照前3 d以蜂胶灌胃,每天1次,剂量为0.2 g/kg;蜂胶治疗组以同样剂量于受照当天开始给药,连续7d,每天1次。辐射组灌服等量蒸馏水。实验组大鼠同时接受一次性全身γ射线照射,剂量为3.0Gy,剂量率1.0Gy/min。（2）氡染毒实验:雄性Wistar大鼠28只,随机分为7个组（1个对照组,3个染氡组,3个蜂胶处理组）,每组4只。染氡组分低、中、高3个剂量,染氡剂量分别为30,67,111WLM。3个蜂胶处理组染氡剂量与氡处理组相同,但在每次染氡前灌服蜂胶0.2g/kg,灌服总量分别为0.39g、0.93g、1.44g。（3）采用黄嘌呤氧化酶法-羟胺法测定各组大鼠外周血及肺匀浆的超氧化酶歧化酶（superoxide dismutase,SOD）活性,硫代巴比妥酸法（thiobarituric acid,TBA）测定丙二醛（malondialdehyde,MDA）的含量;HE染色观察肺组织形态学变化;采用单细胞凝胶电泳（single cell gel electrophoresis,SCGE）技术检测大鼠外周血细胞及肺灌洗液细胞（bronchoalveolar lavage fluid,BALF）DNA损伤;以3H-TdR掺入法检测染氡组大鼠淋巴细胞增殖率。结果:（1）氧化损伤效应:⁶⁰Co-γ射线照射实验中,照射前﹑后给予蜂胶均可提升大鼠血清SOD活性,降低MDA含量。在氡染毒实验中,染氡组大鼠的外周血以及肺组织中SOD活性随着染氡剂量的增加而降低,MDA含量呈现相反方向变化。蜂胶处理组与相应的染氡组相比SOD活性均上升,MDA含量下降。病理切片观察,随着染氡剂量的增加,染氡组肺支气管上皮细胞核增大,染色较深,纤毛增长后逐渐缩短;高剂量时,部分上皮细胞及纤毛脱落。蜂胶处理组与染氡组相比,细胞核染色较浅,纤毛模糊。（2）遗传损伤效应:⁶⁰Co-γ射线照射实验中,照射后大鼠外周血白细胞DNA尾长及尾DNA%含量均显著增加;蜂胶预防组DNA尾长及尾DNA%含量则明显减少。氡染毒实验中,随着染氡剂量的加大,大鼠肺灌洗液细胞的DNA尾长及尾DNA%含量增加。蜂胶处理组中,除低剂量染氡+蜂胶组外,其余各组DNA尾长和尾DNA%含量与相应染氡组相比显著降低。（3）外周血改变:⁶⁰Co-γ射线照射试验,照后4d,7d,蜂胶预防组和蜂胶治疗组外周更多还原

【Abstract】 Objective:To study the protective effects of propolis in rats exposed to ⁶⁰Co–γrays and radon inhalation .Metheods: （1）Male Wistar rats were randomly divided into 3 groups with 6 rats in each group,i.e.,irradiation group, prevention group and therapy group.The prevention group was given propolis per day before irradiation at the dose of 0.2mg/kg in 3 consecutive days.The therapy group was given propolis after irradiation at the same dose in 7 consecutive days.The experimental groups were exposed ⁶⁰Co-γrays at the dose of 3.0Gy and dose rate of 1.0Gy/min. （2）Twenty-eight male Wistar rats were randomly divided into 7 groups,one control group,three groups of radon exposure（the cumulative doses up to 30,67 and 111WLM, respectively） and three groups of propolis prevention.The prevention groups were given propolis at the dose of 0.2mg/kg before daily radon exposure. （3）The activity of SOD（superoxide dismutase） and the content of MDA（malondialdehyde）in blood and lung tissue were detected. Pathological sections were used to identify the lung damage induced by radon. DNA damage of BALF（bronchoalveolar lavage fluid） cells and WBC（white blood cell） were detected by SCGE（single cell gel electrophoresis）. The propolis effects on the peripheral blood cells were also observed .Results: （1） The activity of SOD in rats treated with propolis after exposure to ⁶⁰Co-γrays was higher and the content of MDA was lower than those in irradiation group. The activity of SOD in blood and lung tissue was significantly decreased and the level of MDA increased in radon-inhald rats compare to the control group.The activity of SOD was increased and the content of MDA was reduced in the propolis prevention groups. Inflammatory reaction was observed in lung tissues after radon exposure. （2） The length of commet tail and the DNA% content in BALF cells and WBC increased after exposure to ⁶⁰Co-γrays and radon irradiation,but decreased after treatment with propolis.（3） The number of WBC in rats treated with propolis increased significantly.更多还原