Elimination of dendritic spines with long-term memory is specific to active circuits.
Elimination of dendritic spines with long-term memory is specific to active circuits.
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DOI：
10.1523/jneurosci.1131-12.2012
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发表时间：
2012-09-05
期刊：
影响因子：
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通讯作者：
Mayford M
中科院分区：
文献类型：
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作者：
Sanders J;Cowansage K;Baumgärtel K;Mayford M
在学习过程中活跃的大脑回路的结构变化被认为对长期记忆存储很重要。如果这些变化支持长期的信息存储，它们可能会出现在学习后的遥远时间点，以及特定于由学习激活的回路，并对行为范式的偶发事件敏感。在这里，我们展示了海马体的这种变化，这是背景恐惧条件反射的结果。恐惧条件化小鼠的活跃神经元上的脊椎明显减少。这种脊椎丢失不会发生在回家的小鼠身上，也不会发生在单独暴露在训练环境中的小鼠身上。暴露在不成对电击下的小鼠表现出脊柱的普遍减少。这些与学习相关的脊椎密度变化可能反映了编码的直接机制，或者也可能反映了对先前描述的由于谷氨酸受体插入而导致的传递增强的代偿性适应。
Structural changes in brain circuits active during learning are thought to be important for long-term memory storage. If these changes support long-term information storage they might be expected to be present at distant timepoints after learning, as well as specific to the circuit activated with learning, and sensitive to the contingencies of the behavioral paradigm. Here, we show such changes in the hippocampus as a result of contextual fear conditioning. There were significantly fewer spines specifically on active neurons of fear-conditioned mice. This spine loss did not occur in homecage mice or in mice exposed to the training context alone. Mice exposed to unpaired shocks showed a generalized reduction in spines. These learning-related changes in spine density could reflect a direct mechanism of encoding or alternately could reflect a compensatory adaptation to previously described enhancement in transmission due to glutamate receptor insertion.