1999) studies showing that some synapses contain Excitatory synapses in the CNS release glutamate, NMDA receptors but no AMPA receptors. which acts primarily on two types of ionotropic recepIn addition to LTP, synapses can also undergo longtors: AMPA receptors and NMDA receptors. AMPA term depression (LTD). A more modest and prolonged receptors mediate the postsynaptic depolarization activation...

Recent studies have shown that NMDA receptors are involved in the tolerance and dependence to opioids. In addition, it has been reported that ketamine, dextromethorphan and amantadine have antagonistic activity at NMDA receptors. Therefore, this study was conducted to clarify the effect of these drugs on morphine withdrawal syndrome. Morphine dependence was induced by increasing doses of morphi...

Although the trafficking of AMPA receptors has received much recent fanfare as a mechanism for synaptic plasticity, NMDA receptors have received less attention in this regard. However, Scott et al. now show that independent regions within the cytoplasmic domains of NMDA receptor type 1 (NR1) and NMDA receptor type 2 (NR2) subunits target NMDA receptors for internalization. Interestingly, the re...

Considerable evidence has accumulated describing a complex interaction between the dopaminergic and glutamatergic pathways. Efforts to describe the mechanisms underlying this complex interaction have implicated a functional interaction between dopamine and glutamate receptors. Classically, the interaction between D(1) and NMDA (N-methyl-D-aspartate) receptors has been proposed to involve the ac...

The involvement of NMDA-type glutamate receptor in neuronal injury established in experimental stroke and neurotrauma models has been recently challenged by failures in treatment of stroke/neurotrauma patients with NMDA receptor antagonists. NMDA receptor activity is known to be essential for mediating a multitude of physiological functions. However, how NMDA receptors are recruited to cause ne...

The N-methyl-D-aspartate (NMDA) receptor plays an essential role in excitatory transmission, synaptic integration, and learning and memory. In the classical view, postsynaptic NMDA receptors act as canonical coincidence detectors providing a 'molecular switch' for the induction of various forms of short- and long-term synaptic plasticity. Over the past twenty years there has been accumulating e...

Infection by the human immunodeficiency virus (HIV) can result in debilitating neurological syndromes collectively known as HIV-associated neurocognitive disorders. Although the HIV coat protein gp120 has been identified as a potent neurotoxin that enhances NMDA receptor function, the exact mechanisms for this effect are not known. Here we provide evidence that gp120 activates two separate sign...

NMDA (N-methyl-D-aspartate) receptors are excitatory neurotransmitter receptors in the brain critical for synaptic plasticity and neuronal development. These receptors are Ca2+-permeable glutamate-gated ion channels whose physiological properties are regulated by intracellular Ca2+. We report here the purification of a 20 kDa protein identified as calmodulin that interacts with the NR1 subunit ...

In this issue of Molecular Pharmacology, Low et al. (2003) delve into the mechanisms by which pH modulates the glutamate receptor subtype specifically activated by N–methylD-aspartate (NMDA). Based on a combination of scanning mutagenesis, patch clamp physiology, and molecular modeling, the authors conclude that amino acids involved in NMDA receptor modulation by protons are clustered in region...

Increasing data suggest that glutamate might act as a cell-signaling molecule in non-neuronal tissues such as the skin. Here we demonstrate the presence of functional N-methyl-D-aspartate (NMDA)-type glutamate receptors in human keratinocytes. NMDA receptor expression strongly reflects the degree of cell-to-cell contact. Wounding polarizes the expression of NMDA receptors in keratinocytes invol...