Long-TermIn VivoImaging of Dendritic Spines in the Hippocampus Reveals Structural Plasticity

• DOI: 10.1523/jneurosci.1464-14.2014
• Publication Date: 2014-10-15T17:14:20Z
• Authors: Ligang Gu; Stefanie Kleiber; Lena Schmid; Felix Nebeling; Miriam Chamoun; Julia Steffen; Jens Wagner; Martin Fuhrmann
• Keywords: Entorhinal cortex

Hippocampal function is important for learning and memory. During memory processing, hippocampal CA1 neurons play a crucial role by integrating excitatory synaptic input from CA3 the entorhinal cortex. These receive almost exclusively on dendritic spines. The formation elimination—structural plasticity—of spines reflect wiring changes within network. Despite relevance of hippocampus in memory, most vivo data structural plasticity derive cortical regions. We established chronic window approach using two-photon microscopy to visualize throughout all layers over time course weeks. Moreover, even granule cells dentate gyrus could be reliably detected. found that spine density stratum radiatum (∼1.1 per micrometer) remained stable However, small fraction (3.4%) were formed eliminated between imaging sessions, which demonstrated exhibit adult mice. In addition, we tested possible inflammatory or behavioral side effects implantation. Mice exhibited transient increase microgliosis astrogliosis, declined few did not detect any difference performance an open-field contextual fear-conditioning paradigm. conclusion, long-term revealed pyramidal neurons. This may provide powerful tool analyze neuronal network rewiring during processes health disease.