Mechanisms of hippocampal long-term depression are required for memory enhancement by novelty exploration.
Mechanisms of hippocampal long-term depression are required for memory enhancement by novelty exploration.
复制标题
海马长期抑郁的机制是通过新奇探索增强记忆所必需的
DOI：
10.1523/jneurosci.0984-12.2012
复制
发表时间：
2012-08-29
期刊：
影响因子：
--
通讯作者：
Wang YT
中科院分区：
文献类型：
--
作者：
Dong Z;Gong B;Li H;Bai Y;Wu X;Huang Y;He W;Li T;Wang YT
众所周知，新奇的环境可以增强学习和记忆。然而，其根本机制仍知之甚少。在这里，我们报告说，在自由活动的大鼠中，新奇探索促进了海马 CA1 长期抑制 (LTD) 的产生，这是一种特征明确的突触可塑性形式，被认为是空间学习的细胞基础，从而在抑制性回避学习过程中将短期记忆 (STM) 转化为长期记忆 (LTM)。用两种机制和结构不同的抑制剂阻断 CA1 LTD 的诱导或表达不仅可以防止新颖性的获得，还可以防止新颖性探索促进的 STM 向 LTM 的转化。此外，通过强电刺激诱导方案产生LTD或通过药理学抑制谷氨酸转运蛋白活性促进海马LTD的产生模仿新奇探索的行为效果，充分促进STM向LTM的转化。总之，我们的研究结果表明，LTD 的诱导不仅在新奇事物的习得中发挥着重要作用，而且在新奇事物介导的记忆增强中也发挥着重要作用。
It is well known that novel environments can enhance learning and memory. However, the underlying mechanisms remain poorly understood. Here, we report that, in freely moving rats, novelty exploration facilitates the production of hippocampal CA1 long-term depression (LTD), a well characterized form of synaptic plasticity believed to be a cellular substrate of spatial learning, and thereby converts short-term memory (STM) into long-term memory (LTM) in an inhibitory avoidance learning procedure. Blocking the induction or the expression of CA1 LTD with two mechanistically and structurally distinct inhibitors prevents not only novelty acquisition but also the novelty exploration-promoted conversion of STM into LTM. Moreover, production of LTD with a strong electrical stimulation induction protocol or facilitation of hippocampal LTD by pharmacological inhibition of glutamate transporter activity mimics the behavioral effects of novelty exploration, sufficiently promoting the conversion of STM into LTM. Together, our findings suggest that induction of LTD may play an essential role not only in novelty acquisition but also in novelty-mediated memory enhancement.