Cell Assemblies in the Cortico-Hippocampal-Reuniens Network during Slow Oscillations

David Angulo-Garcia (1) , Maëva Ferraris (2, 3) , Antoine Ghestem (2, 3) , Lauriane Nallet-Khosrofian (2, 3) , Christophe Bernard (2, 3) , Pascale P Quilichini (2, 3)

1 Grupo de Modelado Computacional,Instituto de Matematicas Aplicadas, Universidad de Cartagena
2 INS - Institut de Neurosciences des Systèmes
3 AMU - Aix Marseille Université

The nucleus reuniens (NR) is an important anatomic and functional relay between the medial prefrontal cortex (mPFC) and the hippocampus (HPC). Whether the NR controls neuronal assemblies, a hallmark of information exchange between the HPC and mPFC for memory transfer/consolidation, is not known. Using simultaneous local field potential and unit recordings in NR, HPC, and mPFC in male rats during slow oscillations under anesthesia, we identified a reliable sequential activation of NR neurons at the beginning of UP states, which preceded mPFC ones. NR sequences were spatially organized, from dorsal to ventral NR. Chemical inactivation of the NR disrupted mPFC sequences at the onset of UP states as well as HPC sequences present during sharp-wave ripples. We conclude that the NR contributes to the coordination and stabilization of mPFC and HPC neuronal sequences during slow oscillations, possibly via the early activation of its own sequences.

Mots clés: cell assemblies; hippocampus; network; nucleus reuniens; medial prefrontal cortex; slow oscillations

Domaines: Neurobiologie

David Angulo-Garcia, Maëva Ferraris, Antoine Ghestem, Lauriane Nallet-Khosrofian, Christophe Bernard, et al.. Cell Assemblies in the Cortico-Hippocampal-Reuniens Network during Slow Oscillations. Journal of Neuroscience, 2020, 40, pp.8343 - 8354. ⟨10.1523/jneurosci.0571-20.2020⟩. ⟨hal-03582770⟩