Afferent information initiating the cardiorespiratory responses during nasal stimulation projects from the nasal passages to neurons within the trigeminal medullary dorsal horn (MDH) via the anterior ethmoidal nerve (AEN). Central AEN terminals are thought to release glutamate to activate the MDH neurons. This study was designed to determine which neurotransmitter receptors (AMPA, kainate, or N...

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...

Activation of ionotropic glutamate receptors of the AMPA and NMDA subtypes likely contributes to neuronal injury and death in various neurodegenerative disorders. Excitotoxicity can manifest as either apoptosis or necrosis, but the mechanisms that determine the mode of cell death are not known. We now report that levels of AMPA receptor subunits GluR-1 and GluR-4 are rapidly decreased in cultur...

NMDA receptors are composed of two GluN1 (N1) and two GluN2 (N2) subunits. Constituent N2 subunits control the pharmacological and kinetic characteristics of the receptor. NMDA receptors in hippocampal or cortical neurons are often thought of as diheteromeric, meaning that they contain only one type of N2 subunit. However, triheteromeric receptors with more than one type of N2 subunit also have...

Inhibition of N-methyl-D-aspartate (NMDA) receptors has been viewed as a primary cause of xenon anesthesia, yet the mechanism is unclear. Here, we investigated interactions between xenon and the ligand-binding domain (LBD) of a NMDA receptor and examined xenon-induced structural and dynamical changes that are relevant to functional changes of the NMDA receptor. Several comparative molecular dyn...

NMDA receptor antagonists can induce a schizophrenia-like psychosis, but the role of NMDA receptors in the pathophysiology of schizophrenia remains unclear. Expression patterns of mRNAs for five NMDA receptor subunits (NR1/NR2A-D) were determined by in situ hybridization in prefrontal, parieto-temporal, and cerebellar cortex of brains from schizophrenics and from neuroleptic-treated and nonmedi...

NMDA receptor activity is important for many physiological functions, including synapse formation and alterations in synaptic strength. NMDA receptors are composed most commonly of NR1 and NR2 subunits. There are four NR2 subunits (NR2A-NR2D). NR2 subunit expression varies across both brain regions and developmental stages. The identity of the NR2 subunit within a functional NMDA receptor helps...

objective(s) in this study we investigated the expression of gabaa receptor subunits during brain development. these receptors may change in the embryonic chick forebrain. materials and methodes the expression levels of four types of gabaa receptor gamma subunits (γ1, γ2, γ3 and γ4) were quantified in the embryonic chick forebrain at 32 hr, 3, 7, 14, and 20 days of incubation and day one after ...

Multiple epsilon subunits are major determinants of the NMDA receptor channel diversity. Based on their functional properties in vitro and distributions, we have proposed that the epsilon 1 and epsilon 2 subunits play a role in synaptic plasticity. To investigate the physiological significance of the NMDA receptor channel diversity, we generated mutant mice defective in the epsilon 2 subunit. T...