Synaptic Islands Defined by the Territory of a Single Astrocyte

In the mammalian brain, astrocytes modulate neuronal function, in part, by synchronizing neuronal firing and coordinating synaptic networks. Little, however, is known about how this is accomplished from a structural standpoint. To investigate the structural basis of astrocyte-mediated neuronal synchrony and synaptic coordination, the three-dimensional relationships between cortical astrocytes and neurons was investigated. Using a transgenic and viral approach to label astrocytes with enhanced green fluorescent protein, we performed a three-dimensional reconstruction of astrocytes from tissue sections or live animals in vivo. We found that cortical astrocytes occupy nonoverlapping territories similar to those…

• NI
  National Institutes of Health