Calcium signalling in astrocytes and modulation of neural activity

Up to few years ago astrocytes have been considered as passive elements of brain, providing structural and metabolic support to the neurons, but playing little role in information processing. However, astrocytes express a wide variety of neurotransmitter receptors and recent researches revealed that astrocytes located near synapses respond to neurotransmitters (including glutamate, GABA, ATP etc.) with the elevation of their internal calcium levels [1-6]. The increase of the calcium level in these cells then mediates the release of glutamate and other neuroactive substances (feedback mechanism) capable to modulate the synaptic communication between neurons [7]. In particular, a relevant process is the release from astrocytes of ATP and glutamate. ATP is an important neurotransmitter and in turn its action on astrocytes is mediated by ionotropic (P2X) and metabotropic (P2Y) purinoreceptors [7, 8]; there is evidence that the release of ATP at the presynaptic site contributes to synaptic...

• Type: Journal
• Year: 2007
• Where: BIOSYSTEMS
• Authors: Angelo Di Garbo, Michele Barbi, Santi Chillemi, Susanna Alloisio, Mario Nobile
• Keywords: Astrocytes, BIOSYSTEMS 2007, Calcium Level, Glutamate