摘要目的:探讨海马旁下托兴奋性神经元在视空间记忆中的作用。方法:16只6~8周龄成年雄性C57BL/6小鼠按照随机数字表法分为对照组和实验组，实验组于双侧海马旁下托分别注射0.4 μl AAV5-CaMKⅡα-eNpHR3.0-eYFP病毒，对照组注射等量AAV5-CaMKⅡα-eYFP病毒，病毒注射6周后进行光纤埋植。小鼠适应1周后进行实验，在给予持续黄光抑制海马旁下托谷氨酸能神经元活性的同时进行新奇物体位置识别实验，观察两组小鼠视空间记忆功能(以D2值进行衡量)及c-fos阳性细胞数的差异。采用SPSS 20.0进行数据分析，采用独立样本 t检验或配对 t检验分析组间及组内差异。 结果:新奇物体位置识别实验结果表明，在学习阶段，对照组小鼠和实验组小鼠对新旧物体的探索时间比均差异无统计学意义[对照组：(0.51±0.06)，(0.49±0.04)， t＝1.21， P>0.05；实验组：(0.49±0.05)，(0.50±0.04)， t＝-0.78， P>0.05]。实验组小鼠的视空间记忆功能明显低于对照组，差异有统计学意义[D2值：(0.26±0.07)，(0.55±0.06)， t＝-2.96， P<0.05]。c-fos荧光染色表明，实验组小鼠C-fos阳性细胞数[(96.33±7.13)个]明显少于对照组[(127.67±5.24)个]，差异有统计学意义( t＝-3.54， P<0.05)。 结论:抑制海马旁下托谷氨酸能神经元活性导致小鼠视空间记忆功能下降，表明海马旁下托谷氨酸能神经元参与了视空间记忆功能。

abstractsObjective:To investigate the function of glutamatergic neuron of the parasubiculum in spatial memory.Methods:Sixteen adult male C57BL/6 mice aged 6-8 weeks were divided into two groups randomly, 0.4 μl AAV5-CaMKⅡα-eNpHR3.0-eYFP was injected into the bilateral parasubiculum respectively in experimental group, equal dose AAV5-CaMKⅡα-eYFP for control group.The optic fiber was implanted 6 weeks after virus injection.The novel object place recognition test was performed one week after optic fiber implantation, continuous yellow light was delivered during the behavioral test to inhibit the function of glutamatergic neuron in the parasubiculum.The standard memory index (D2) was used to evaluate the spatial memory function.SPSS 20.0 software was used to process the data, and the independent-samples t-test and paired-samples t-test were used for data analysis. Results:In the novel object place recognition experiment, the mice showed no preference for either object in both control group(new object: 0.51±0.06, familiar object: 0.49±0.04, t=1.21, P>0.05) and experimental group(new object: 0.49±0.05, familiar object: 0.50±0.04, t=-0.78, P>0.05). Compared with the control group (0.55±0.06), the D2 score of the experimental group (0.26±0.07) was significantly lower ( t=-2.96, P<0.05), and the number of c-fos positive neuron in experimental group (96.33±7.13) was also significantly less than that in control group (127.67±5.24, t=-3.54, P<0.05). Conclusion:Inhibiting glutamatergic neuronal activity in the parasubiculum impairs spatial memory in mice, suggesting that glutamatergic neurons of the parasubiculum play an important role in spatial memory.