Yasuda Masahiro, Mayford Mark R
The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
Neuron. 2006 Apr 20;50(2):309-18. doi: 10.1016/j.neuron.2006.03.035.
To investigate the role of the entorhinal cortex in memory at a molecular level, we developed transgenic mice in which transgene expression was inducible and limited to the superficial layers of the medial entorhinal cortex, pre- and parasubiculum. We found that expression of a constitutively active mutant form of CaMKII in these structures disrupted spatial memory formation. Immediate post-training activation of the transgene disrupted previously established memory while transgene activation 3 weeks following the training was ineffective. These results demonstrate that, similar to the hippocampus, the entorhinal cortex plays a time-limited role in spatial memory formation but is not a final cortical repository of long-term memory. Moreover, these results suggest that the indiscriminate activation of CaMKII is able to disrupt preexisting memories, possibly by altering the pattern of synaptic weight changes that are thought to form the basis of the memory trace.
为了在分子水平上研究内嗅皮层在记忆中的作用，我们构建了转基因小鼠，其中转基因表达是可诱导的，并且局限于内侧内嗅皮层、前下托和下托的浅层。我们发现，在这些结构中组成型活性突变形式的CaMKII的表达破坏了空间记忆的形成。训练后立即激活转基因会破坏先前建立的记忆，而训练3周后激活转基因则无效。这些结果表明，与海马体类似，内嗅皮层在空间记忆形成中发挥着限时作用，但不是长期记忆的最终皮层储存库。此外，这些结果表明，CaMKII的无差别激活能够破坏已有的记忆，可能是通过改变被认为构成记忆痕迹基础的突触权重变化模式来实现的。
