TY - JOUR T1 - Spatial Organization of Neuron-Astrocyte Interactions in the Somatosensory Cortex JF - bioRxiv DO - 10.1101/2022.02.03.479046 SP - 2022.02.03.479046 AU - Andrés M. Baraibar AU - Lindsey Belisle AU - Giovanni Marsicano AU - Carlos Matute AU - Susana Mato AU - Alfonso Araque AU - Paulo Kofuji Y1 - 2022/01/01 UR - http://biorxiv.org/content/early/2022/02/05/2022.02.03.479046.abstract N2 - Microcircuits in the neocortex are functionally organized along layers and columns, which are the fundamental modules of cortical information processing. While the function of cortical microcircuits has focused on neuronal elements, much less is known about the functional organization of astrocytes and their bidirectional interaction with neurons. Here we show that CB1R-mediated astrocyte activation by neuron-released endocannabinoids elevate astrocyte Ca2+ levels, stimulate ATP/adenosine release as gliotransmitters, and transiently depress synaptic transmission in layer 5 pyramidal neurons at relatively distant synapses (>20 µm) from the stimulated neuron. This astrocyte-mediated heteroneuronal synaptic depression occurred between pyramidal neurons within a cortical column and was absent in neurons belonging to adjacent cortical columns. Moreover, this form of heteroneuronal synaptic depression occurs between neurons located in particular layers, following a specific connectivity pattern that depends on a layer-specific neuron-to-astrocyte signaling. These results unravel the existence of astrocyte-mediated non-synaptic communication between cortical neurons, and that this communication is column- and layer-specific, which adds further complexity to the intercellular signaling processes in the cortex.Competing Interest StatementThe authors have declared no competing interest. ER -