Department of Medical Microbiology, Immunology and Cell Biology, Southern Illinois University School of Medicine Springfield, IL, USA ; Department of Neurology, Southern Illinois University School of Medicine Springfield, IL, USA.
Front Neural Circuits. 2013 Oct 21;7:165. doi: 10.3389/fncir.2013.00165. eCollection 2013.
The mammalian hippocampus functions to encode and retrieve memories by transiently changing synaptic strengths, yet encoding in individual subregions for transmission between regions remains poorly understood. Toward the goal of better understanding the coding in the trisynaptic pathway from the dentate gyrus (DG) to the CA3 and CA1, we report a novel microfabricated device that divides a micro-electrode array into two compartments of separate hippocampal network subregions connected by axons that grow through 3 × 10 × 400 μm tunnels. Gene expression by qPCR demonstrated selective enrichment of separate DG, CA3, and CA1 subregions. Reconnection of DG to CA3 altered burst dynamics associated with marked enrichment of GAD67 in DG and GFAP in CA3. Surprisingly, DG axon spike propagation was preferentially unidirectional to the CA3 region at 0.5 m/s with little reverse transmission. Therefore, select hippocampal subregions intrinsically self-wire in anatomically appropriate patterns and maintain their distinct subregion phenotype without external inputs.
哺乳动物的海马体通过短暂改变突触强度来编码和检索记忆，但对于个体亚区的编码以在区域之间进行传递仍知之甚少。为了更好地理解从齿状回（DG）到 CA3 和 CA1 的三突触通路中的编码，我们报告了一种新颖的微制造设备，该设备将微电极阵列分为两个隔室，分别是通过穿过 3×10×400μm 隧道生长的轴突连接的独立海马体网络亚区。qPCR 的基因表达显示了单独的 DG、CA3 和 CA1 亚区的选择性富集。DG 与 CA3 的重新连接改变了爆发动力学，这与 DG 中 GAD67 和 CA3 中 GFAP 的显著富集有关。令人惊讶的是，DG 轴突的尖峰传播在 0.5 m/s 时优先向 CA3 区域单向进行，而反向传输很少。因此，选择的海马体亚区内在地以解剖上适当的模式自我连接，并在没有外部输入的情况下保持其独特的亚区表型。
