+15Gz重复暴露7d对小鼠学习记忆功能和心理状态的影响

Effects of repeated +15 Gz exposure for 7 d on learning, memory and psychological state of mice

目的探讨连续7 d高正加速度(+Gz)暴露对C57BL/6小鼠学习记忆能力和心理状态的影响。方法采用动物离心机对小鼠连续7 d进行+15 Gz、15 min/d暴露。7 d暴露后,利用水迷宫实验检测+15 Gz暴露对小鼠空间学习记忆能力的影响;利用旷场和高架十字迷宫实验检测+15 Gz暴露对于小鼠恐惧和焦虑情绪的影响;建立场景性恐惧条件化模型,利用僵立时间占总测试时间的百分比来评估小鼠的恐惧记忆程度。结果(1)在水迷宫实验中,+15 Gz组小鼠的空间学习能力和记忆能力明显高于对照组小鼠(P<0.05,P<0.01)。(2)旷场和高架十字迷宫实验证明,+15 Gz重复暴露能够显著减少小鼠的焦虑与恐惧状态(P<0.01)。(3)在场景性恐惧记忆检测中,+15 Gz组小鼠僵立时间占总测试时间百分比明显低于对照组小鼠(P<0.01)。结论+15 Gz连续暴露7 d能够显著增强小鼠的空间学习和记忆能力,并减少焦虑恐惧情绪和场景性恐惧记忆能力。

Objective To investigate the effects of repeated +Gz exposure for 7 d on learning, memory and psychological state of C57 BL/6 mice. Methods Mice were exposed to +15 Gz for 7 d(15 min/d) through animal centrifuge. After 7 d exposure, Morris water maze test was used to detect the effect of +15 Gz exposure on spatial learning and memory of mice;the open field and elevated plus maze test were used to detect the effect of +15 Gz on the anxiety and fear of mice. A scenario-based fear conditioning model was established and the percentage of freezing time in total test time was utilized to assess the degree of contextual fear memory in mice. Results(1)In Morris water maze test, the spatial learning and memory ability of +15 Gz group was significantly higher than that of the control group(P<0.05, P<0.01).(2)The open field and elevated plus maze test proved that repeated +15 Gz treatment could significantly reduce the state of anxiety and fear of mice(P<0.01).(3)In the fear conditioning analysis, the percentage of freezing time in total test time in +15 Gz group was significantly lower than that of the control group(P<0.01). Conclusion The repeated +15 Gz exposure for 7 d could significantly enhance the spatial learning ability of mice, and lessen anxiety and fear as well as contextual fear memory of mice.