全脑照射后昆明鼠的学习、记忆力损伤及其变化规律

Dynamic changing of mouse learning and memory ability after whole brain irradiation

目的 探讨全脑照射后鼠的学习、记忆力损伤及其变化规律。方法 硫喷妥钠麻醉后 ,采用直线加速器 10MeV电子线照射 10 2只 4～ 6周龄昆明鼠全脑 ;10 2只分为 3组 (每组 34只 ) ,照射剂量分别为 2 0、10、5Gy。另设 34只鼠为对照组 (只麻醉不照射 )。照射后第 1、2、3、4、5天和第 14、2 8、5 6、84天采用跳台法测定鼠的学习、记忆力。结果 照射后第 2、3、5 6天 ,2 0Gy组鼠受电击次数分别为 (1 0± 0 9)次、(0 9± 0 6 )次和 (1 4± 1 0 )次 ,与对照组的差异均有非常显著性 (P <0 0 1)。照射后第 2 ,3天 2 0Gy组受电击潜伏期分别为 (6 4± 87)s、(92± 78)s,与对照组 [(173± 2 1)s ,(175± 16 )s]的差异均有非常显著性 (P <0 0 1) ;第 5 6天为 (16 4± 88)s ,与对照组 [(2 6 1± 79)s]的差异有显著性 ,P <0 0 5。照射后第 2天 2 0Gy组受电击鼠的构成比为 6 / 9,与对照组 (11% )的差异有显著性 (P <0 0 5 )。2 0Gy组学习、记忆力损伤最重 ,10Gy组次之 ,5Gy组与对照组的差异无显著性。照射后鼠学习、记忆力损伤的规律 :照射后第 2 ,3天学习、记忆力有明显损伤 ,第 4～ 2 8天为暂时恢复期 ,第 5 6天出现第 2次损伤高峰 ,第 84天后再次恢复。结论 放射性脑损伤可使鼠的学习、记忆力明显下降 ,记?

Objective To study the regularity of the injury of the mose learning and memory ability, after the whole brain irradiation Methods After anaesthetized with thiopentone, the whole brain of Kunming mice was irradiated with 10 MeV electronic ray On the first, second, third, fourth, fifth,fourteenth, twenty eighth, fifty sixth and eighty fourth day after the irradiation, the mouse learning and memory ability was measured with step down method Results On the second,third and fifty sixth day after the brain irradiation with 20 Gy electronic ray, the means of errors of the mice were 1 0±0 9, 0 9±0 6 and 1 4±1 0 respectively,all were different significantly compared with control In those days, the mean latencies of step down of the mice were( 64±87)s, (92±78)s and (164±88)s, all were shorter than that of the control On the fourth, fifth, fourteenth, twenty eighth and eight fourth day after the irradiation, the mean number of errors and the median latencies of step down of the mice were not different from the control The learning and memory ability of the mice with 20 Gy irradiation was injured apparently, that with 10 Gy irradiation also injured, but that with 5 Gy irradiation was not different from the control Conclusions The learning and memory ability of the mouse is injured by brain irradiating The degree of memory impairment and recovery is corresponding to the irradiation dose