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In the central nervous system, (Na+ + K+)-coupled glutamate transporters restrict the neurotoxicity of this transmitter and limit the duration of synaptic excitation at some synapses. The various isotransporters exhibit a particularly high homology in an extended hydrophobic domain of ill-defined topology that contains several determinants involved in ion and transmitter binding. Here, we descr...

We first measured the effects of trace levels of an endocrine disruptor, tributyltin (TBT), on the secretion response from nerve cells using a microfabricated biosensor designed for the continuous measurement of L-glutamate and hydrogen peroxide. We observed higher and long-lasting glutamate and hydrogen peroxide concentrations from the cells when cultured rat cortical neurons were exposed to T...

Glutamate receptor (GluR)-mediated neurotoxicity is implicated in a variety of disorders ranging from ischemia to neural degeneration. Under conditions of elevated glutamate, the excessive activation of GluRs causes internalization of pathologic levels of Ca, culminating in bioenergetic failure, organelle degradation, and cell death. Efforts to characterize cellular and molecular aspects of exc...

Recent studies show that glutamate transporter-mediated currents occur in astrocytes when glutamate is released from hippocampal synapses. These transporters remove excess glutamate from the extracellular space, thereby facilitating synaptic input specificity and preventing neurotoxicity. Little is known about the position of astrocytic processes at hippocampal synapses. Serial electron microsc...

The use of low doses of naltrexone for the treatment of multiple sclerosis (MS) enjoys a worldwide following amongst MS patients. There is overwhelming anecdotal evidence, that in low doses naltrexone not only prevents relapses in MS but also reduces the progression of the disease. It is proposed that naltrexone acts by reducing apoptosis of oligodendrocytes. It does this by reducing inducible ...

Mammalian neurolathyrism is a progressive and degenerative disease of central nervous system originating from excessive consumption of Lafhyrus seeds, particularly those of L. sativus. Rao et al. [I] have isolated P-N-oxalyl-L-a&diaminopropionic acid (ODAP) from the seeds of L. satiuus and shown this substance to be the neurotoxin [ 1, 21 Characterization of the biochemical effect and cellular ...

Four L-glutamate neurotransmitter transporters, the three Na(+)-dependent GLAST-1, GLT-1 and EAAC-1, and the Cl(-)-dependent EAAT-4, form a new family of structurally related integral plasma membrane proteins with different distribution in the central nervous system. They may have pivotal functions in the regulation of synaptic L-glutamate concentration during neurotransmission and are believed...

Neuritic regression and cell death (neurodegeneration) are common features of both normal nervous system development and neurodegenerative disorders. Growth factors and excitatory amino acid neurotransmitters have been suggested independently to play roles in neurodegenerative processes. The present study investigated the combined effects of fibroblast growth factor (FGF) and glutamate on the d...

BACKGROUND The glutamate model of schizophrenia proposes that altered glutamatergic neurotransmission is fundamental to the development of the disorder. In addition, its potential to mediate neurotoxicity raises the possibility that glutamate dysfunction could underlie neuroanatomic changes in schizophrenia. Here we determine whether changes in brain glutamate are present in subjects at ultra h...