Astrocytes express a wide range of G-protein coupled receptors that trigger release of intracellular Ca2+, including P2Y, bradykinin and protease activated receptors (PARs). By using the highly sensitive sniffer-patch technique, we demonstrate that the activation of P2Y receptors, bradykinin receptors and protease activated receptors all stimulate glutamate release from cultured or acutely diss...

Glutamate receptors are the most common excitatory neurotransmitter receptors in the central nervous system (CNS). Excessive stimulation of glutamate receptors, including receptors of the AMPA and kainate families, is believed to contribute to the neurodegeneration encountered in stroke, CNS trauma, and several degenerative neurologic disorders. Animal models also suggest that AMPA and kainate ...

We hypothesized that cystine/glutamate transporters (xCTs) might be critical regulators of ambient extracellular glutamate levels in the nervous system and that misregulation of this glutamate pool might have important neurophysiological and/or behavioral consequences. To test this idea, we identified and functionally characterized a novel Drosophila xCT gene, which we subsequently named "gende...

In the nervous system, glutamate is an excitatory aminoacid which at higher concentrations has been implicated in a number of disorders. Glutamate is stored in presynaptic vesicles and is released by calcium-dependent exocytosis. After its action on ionotropic receptors (iGluR, related to ionic channels) or metabotropic receptors (mGluR, related to metabolic formation of second messengers), glu...

Glutamatergic synapses, which comprise the majority of excitatory synapses in the mammalian central nervous system, function by presynaptic release of glutamate onto postsynaptic glutamate receptors. At the postsynaptic site, the molecular interactions between glutamate receptors and various intracellular proteins suggest an intimate relationship between synaptic structure and function, and may...

L-glutamate, the major excitatory neurotransmitter in the human brain, activates a family of ligand-gated ion channels, the major subtypes of which are named AMPA, kainate, and NMDA receptors. In common with many signal transduction proteins, glutamate receptors are modulated by ions and small molecules, including Ca(2+), Mg(2+), Zn(2+), protons, polyamines, and steroids. Strikingly, the activa...

On the basis of a large body of experimental data showing that pharmacological modulation of glutamate receptors has a great impact on ischemia-induced neuronal death, excessive activation of glutamate receptors is widely accepted as one of the most important determinants in the development of tissue damage produced by cerebral ischemia (1). In spite of this evidence, howe v e r, how energy dep...

The neural cell adhesion molecule (NCAM) and its associated glycan polysialic acid play important roles in the development of the nervous system and N-methyl-D-aspartate(NMDA)receptor-dependent synaptic plasticity in the adult. Here, we investigated the influence of polysialic acid on NMDA receptor activity. We found that glutamate-elicited NMDA receptor currents in cultured hippocampal neurons...