Neuronal exocytotic release of glutamate at synapses involves a highly specialized vesicular apparatus, consisting of a variety of proteins connected to the vesicles or required for vesicular fusion to the presynaptic membrane. Astrocytes also release glutamate, and recent evidence indicates that this release can modify neuronal function. Several mechanisms have been proposed for astrocytic release of glutamate under pathological conditions, such as reversal of glutamate transporters and opening of volume sensitive ion channels. In this review we limit our discussion to findings supporting the exocytotic release of glutamate, as well as two new pathways implicated in this release, the ionotropic (P2X) purinergic receptors and gap junction hemichannels.
- Connexin " hemichannels"
- Glutamate release
- P2X receptors
- Vesicular glutamate transporters
ASJC Scopus subject areas
- Cellular and Molecular Neuroscience
- Cell Biology