胎次、性别对成年小鼠海马齿状回神经发生及学习记忆的影响

摘要

Objective To evaluate the effects of parity and gender on neurogenesis of hippocampal dentate gyrus and the ability of learning and memory of adult mice.Methods Morris water maze test was used to assess the differences of learning and memory ability between the adult mice born in the first to third parities.The differences of neurogenesis were examined with BrdU-labeled hippocampual dentate gyrus of the adult mice.Results (1) The learning and memory ability (LMA) of mice born in the 2nd parity was significantly higher than that of the 1 st and 3rd parity (P ＜ 0.05) in the same sex,that was LMA2 ＞ LMA1 ＞ LMA3.Besides,female mice had better learning and memory ability than the male mice,(P ＞ 0.05).(2) The number of BrdU-positive hippocampal cells of the mice born in the 2nd parity was higher than that of the 1 st and 3rd parity in the same sex,but the difference was non-significant (P ＞ 0.05),and BrdU-positive cells of the female mice was higher than that in the male mice,but also with a non-significant difference.Conclusions There are essential differences in the neurogenesis of hippocampal dentate gyrus and the learning and memory ability in adult mice of different gender and born in different parities.Therefore,it should be considered to use mice of the same gender and born at the same parity in relevant experimental studies.%目的 探讨胎次、性别是否对成年小鼠海马齿状回神经发生及学习记忆产生影响.方法 运用Morris水迷宫系统检测第1～3胎成年小鼠的学习记忆能力,腹腔注射BrdU,标记神经干细胞,检测不同胎次、性别小鼠海马齿状回中的神经发生的差异.结果 (1)在同性别、不同胎次成年小鼠间,第2胎的学习记忆能力(LMA)均显著地高于第1、3胎的,其影响规律为LMA2＞LMA1＞LMA3,且P＜0.05;在同胎次、不同性别成年小鼠间,雌性小鼠的LMA均高于雄性小鼠的,但其差异无显著性(P＞0.05).(2)在同性别、不同胎次成年小鼠间,第2胎海马DG新生神经细胞的数量(N)均高于第1、3胎的,其影响规律分别为NF2 ＞NF3 ＞NF1和NM2＞ NM1＞NM3,但其差异无显著性(P＞0.05)；在同胎次、不同性别成年小鼠间,雌性小鼠的N均高于雄性小鼠的,但其差异无显著性(P＞0.05).结论 胎次、性别对实验动物神经发生及学习记忆等方面产生的影响是肯定的.因此,在使用实验动物时,应予以充分考虑,尽量使用胎次、性别相同的.