水迷宫训练逆转孕期应激造成的子代海马NR2B表达的降低

Morris water maze training reverses the down-expression of hippocampal NR2B in mice male offspring experienced prenatal stress

目的:比较空间学习记忆中孕期应激子代和对照组子代海马空间学习功能密切相关蛋白NR2B的表达。方法:建立孕期束缚应激小鼠模型,在出生后第3周用酶联免疫法检测子代雄性小鼠血清皮质酮;在出生后第9周,采用免疫蛋白印迹和real-timePCR法检测子代雄性小鼠非空间学习记忆状态及空间学习记忆中海马NR2B的表达水平。结果:(1)基础状态下孕期应激子代血清皮质酮水平与对照组子代并无差异,应激状态下孕期应激子代血清皮质酮水平(43.7×104pg/ml)明显高于对照组子代(18.7×104pg/ml);(2)孕期应激雄性子代在出生后第9周海马NR2B mRNA和蛋白表达均显著低于对照组雄性子代。但经过空间学习记忆训练,两组海马NR2B蛋白水平无明显差异。结论:孕期应激减少子代海马神经元NR2B的表达,但水迷宫行为训练可逆转孕期应激造成的子代海马神经元NR2B的表达降低。

Objective：To explore the effect of Morris water maze training on the expression of hippocampal NR2B in prenatally stressed offspring.Methods：Prenatal restraint stress was used to establish the mice model.The concentration of serum corticosterone was assayed via EIA.The expression of NR2B was determined at mRNA and protein levels by real-time PCR and Western blot respectively,at the postnatal stages of the 3rd and 9th week.After the Morris water training,Western blot was used to assess the level of hippocampal NR2B.Results：（1） There was significant difference between Control and Prenatal stress group under stressed condition,but not under basal condition.（2） The expression of hippocampal NR2B in offspring exposed to prenatal stress was significantly decreased at the postnatal stages of 9th week.But after the Morris water maze training,no difference of hippocampal NR2B was found between two groups.Conclusion：Prenatal stress causes long-lasting down-expression of hippocampal NR2B in prenatally stressed offspring,however,after the Morris water maze training,there is no difference of the level of hippocampal NR2B between Control and Prenatal stress groups.