γ射线和高热对胚胎脑发育的单独及联合作用  

The individual and combined effects of γ rays and hyperthermia on the development of embryonic brains

作　　者：杨业鹏[1] 阮明[2] 刘景院[2] 洪敏 芦春林[2] 

机构地区：[1]北京医科大学放射医学基础教研室,北京100083 [2]北京医科大学公共卫生学院

出　　处：《中国辐射卫生》2000年第2期68-69,共2页Chinese Journal of Radiological Health

摘　　要：目的 :探讨γ射线和高热单独及联合暴露对胚胎脑发育的影响　方法 :对孕 9d小鼠给予 1 0Gy60 Co -γ射线照射或 /和 42℃ 10min高热处理 ,孕 18d剖腹取胎 ,观察胎鼠外观 ,测定胎鼠脑重、全脑细胞数、脑组织核酸及蛋白质含量和作为胆碱能神经元标志的脑组织乙酰胆碱脂酶 (AChE)活力。结果 :各组胎鼠均无神经管畸形发生 ;与对照组比较 ,单纯照射组各指标均显著降低 ,单纯高热组全脑细胞数和AChE活力显著降低 ;先高热处理 ,4h后再照射 ,脑组织AChE活力显著高于单纯照射组 ;先照射 ,后高热处理 ,各指标与单纯照射组无显著差异。结论 :42℃ 10min高热处理对鼠胚胎脑发育的影响远小于 1 0Gyγ照射 ;预先给予高热处理可诱导胚胎对随后给予的γ辐射产生交叉适应性反应 ;先照射 ,后高热处理 。Objective:To observe the individual and combined effects of exposure to γ rays and hyperthermia on the development of embryonic brains.Methods:the pregnant LACA mice were exposed to 1.0 Gy 60 Co-γ rays,42℃ hyperthermia for 10minutes or the two treatments combined together on day 9 of pregnancy.The females were sacrificed on day 18 of pregnancy and the fetuses were gained by cesarean section.The appearance of fetuses was observed and ,then,the weight of fetal brains,the cell number of whole brains,the contents of nucleic acid and protein in brain tissue and the activity of acetylcholine esterase(AChE)in brain tissue as a marker for cholinergic neurons were determined.Results:Nervous tube defects did not occur in all groups.Compared with the control group,all the indices determined significantly declined in the radiation group while the cell number of whole brains and the AChE activity in brain tissue significantly decreased in the hyperthermia group.In the group of hyperthermia in advance,4 hours later,followed by exposure to radiation,the AChE activity in brain tissue was significantly higher than the single radiation group.In the group of prior radiation exposure,4 hours later,followed by hyperthermia,all the indices did not present significant difference from the single radiation group.Conclusion:The effects of 42℃ hyperthermia for 10 minutes on the development of mouse embryo's brains are much weaker than 1.0 Gy γ radiation.It seems that the hyperthermia in advance can induce mouse fetuses to produce the cross adaptability to the following exposure to radiation.Exposure to γ radiation followed by hyperthermia does not present an additive action or a synergistic action.

关 键 词：电离辐射 辐射效应 高热 适应性反应 胚胎脑发育 

分 类 号：R594.1[医药卫生—内科学]