Developmental Profile, Morphology, and Synaptic Connectivity of Cajal-Retzius Cells in the Postnatal Mouse Hippocampus

TY - JOUR

T1 - Developmental Profile, Morphology, and Synaptic Connectivity of Cajal-Retzius Cells in the Postnatal Mouse Hippocampus

AU - Anstötz, Max

AU - Huang, Hao

AU - Marchionni, Ivan

AU - Haumann, Iris

AU - Maccaferri, Gianmaria

AU - Lübke, Joachim H R

N1 - © The Author 2015. Published by Oxford University Press.

PY - 2016/2

Y1 - 2016/2

N2 - Cajal-Retzius (CR) cells are early generated neurons, involved in the assembly of developing neocortical and hippocampal circuits. However, their roles in networks of the postnatal brain remain poorly understood. In order to get insights into these latter functions, we have studied their morphological and synaptic properties in the postnatal hippocampus of the CXCR4-EGFP mouse, where CR cells are easily identifiable. Our data indicate that CR cells are nonuniformly distributed along different subfields of the hippocampal formation, and that their postnatal decline is regulated in a region-specific manner. In fact, CR cells persist in distinct areas of fully mature animals. Subclasses of CR cells project and target either local (molecular layers) or distant regions [subicular complex and entorhinal cortex (EC)] of the hippocampal formation, but have similar firing patterns. Lastly, CR cells are biased toward targeting dendritic shafts compared with spines, and produce large-amplitude glutamatergic unitary postsynaptic potentials on γ-aminobutyric acid (GABA) containing interneurons. Taken together, our results suggest that CR cells are involved in a novel excitatory loop of the postnatal hippocampal formation, which potentially contributes to shaping the flow of information between the hippocampus, parahippocampal regions and entorhinal cortex, and to the low seizure threshold of these brain areas.

AB - Cajal-Retzius (CR) cells are early generated neurons, involved in the assembly of developing neocortical and hippocampal circuits. However, their roles in networks of the postnatal brain remain poorly understood. In order to get insights into these latter functions, we have studied their morphological and synaptic properties in the postnatal hippocampus of the CXCR4-EGFP mouse, where CR cells are easily identifiable. Our data indicate that CR cells are nonuniformly distributed along different subfields of the hippocampal formation, and that their postnatal decline is regulated in a region-specific manner. In fact, CR cells persist in distinct areas of fully mature animals. Subclasses of CR cells project and target either local (molecular layers) or distant regions [subicular complex and entorhinal cortex (EC)] of the hippocampal formation, but have similar firing patterns. Lastly, CR cells are biased toward targeting dendritic shafts compared with spines, and produce large-amplitude glutamatergic unitary postsynaptic potentials on γ-aminobutyric acid (GABA) containing interneurons. Taken together, our results suggest that CR cells are involved in a novel excitatory loop of the postnatal hippocampal formation, which potentially contributes to shaping the flow of information between the hippocampus, parahippocampal regions and entorhinal cortex, and to the low seizure threshold of these brain areas.

U2 - 10.1093/cercor/bhv271

DO - 10.1093/cercor/bhv271

M3 - SCORING: Journal article

C2 - 26582498

VL - 26

SP - 855

EP - 872

JO - CEREB CORTEX

JF - CEREB CORTEX

SN - 1047-3211

IS - 2

ER -