One astrocyte enwraps several neuronal somata. A and B show individual optical sections to reveal the structure of astrocytes expressing EGFP within the dnSNARE mouse (green; left), the location of neurons immunolabeled with anti-NeuN (red; middle), and an overlay (right). Note that the astrocytes contain several holes, which correspond with the locations of neuronal somata. C1, Top-view reconstruction of a single astrocyte (green) and neurons (red). C2, The same cells shown in C1 are depicted in a top-view reconstruction with a threshold mask. Neurons within the astrocytic territory are red (yellow arrows). D, Distribution of the number of neuronal somata that contact one astrocyte. At least 50% of the surface area of a neuron had to make contact with the astrocyte to be considered as having sufficient interaction for inclusion in this analysis. E, F, A single confocal plane of an AAV-transduced astrocyte (green) contacting neuronal somata (red). G, Three-dimensional reconstruction of the astrocyte in E and F.