Multi-scale astrocyte-neuron communication

This chapter reviews studies in the last two decades that led to identifying the rapid bidirectional communication existing between astrocytes and neurons, and its roles in the control of synaptic transmission at local level as well as in the multiscale coordination of large synaptic networks. This chapter first describes the most relevant observations that demonstrated how astrocyte signaling modulates neuronal activity and plasticity, focusing on the role of astrocytic metabotropic receptors, intracellular Ca2+ elevations, and release of glutamate as neuroactive molecule. It then examines evidence of how astrocytes contribute to synaptic networks oscillations and to their behavioral consequences, notably in learning and memory processes. This chapter also discusses recent discoveries about a heterogeneity of the astrocytes, with molecular, morphological and functional differences at both inter- and intra-regional levels, implying a new level of complexity in the modalities by which astrocytes communicate with neurons and participate to brain functions.