Pharmacological studies were performed to determine whether alpha-amino-3-hydroxy-5-methyl-4-isoazoleprionic acid (AMPA)- and/or kainate (KA)-preferring receptors mediate excitatory synaptic inputs to tiger salamander retinal ganglion cells. Excitatory postsynaptic currents (EPSCs), evoked either by light or by stimulating bipolar cells with puffs of K+, were measured using whole cell recording...

Although both protein and mRNAs for kainate receptor subunits are abundant in several brain regions, the responsiveness of AMPA receptors to kainate has made it difficult to demonstrate the presence of functional kainate-type receptors in native cells. Recently, however, we have shown that many hippocampal neurons in culture express glutamate receptors of the kainate type. The large nondesensit...

Experimental evidence supports a number of mechanisms for the synaptic change that occurs with long-term potentiation (LTP) including insertion of AMPA receptors, an increase in AMPA receptor single channel conductance, unmasking silent synapses, and increases in vesicle release probability. Here we combine experimental and modeling studies to quantify the magnitude of the change needed at the ...

–Protein and messenger RNA levels of the AMPA-type glutamate receptor subunits 1–3 are high in many brain regions, but it is not known how much of the glutamate receptor protein is expressed on the surface of neurons in the form of functional receptors. To provide insight into this matter, western blot immunoreactivities for glutamate receptors 1 and 2/3, as well as binding of the specific liga...

The postnatal maturation of glutamatergic synapses involves a change in composition and functional contribution of postsynaptic receptors. Developing cortical synapses are dominated by NMDA receptors (NMDARs) containing NR2B subunits and are characterized by a low ratio of AMPA/NMDA receptor-mediated current. Synapse maturation is marked by the incorporation of NR2A-containing NMDA receptors an...

The biarylpropylsulfonamide class of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) potentiators represented by N-2-(4-(4-cyanophenol)phenol)propyl-2-propanesulfonamide (LY404187) and (R)-4'-[1-fluoro-1-methyl-2-(propane-2-sulfonylamino)-ethyl]-biphenyl-4-carboxylic acid methylamide (LY503430) are positive, allosteric AMPA receptor activators, which enhance AMPA receptor-mediat...

Objective Many antiseizure drugs (ASDs) act on voltage-dependent sodium channels, and the molecular basis of these effects is well established. In contrast, how ASDs level neuronal networks much less understood. Methods present study, we determined eslicarbazepine (S-Lic) different types inhibitory neurons, as motifs. Experiments were performed in hippocampal slices from both sham-control chron...

Cerebellar long-term depression (LTD) is a cellular model system of information storage that may underlie certain forms of motor learning. While cerebellar LTD is expressed as a selective modification of postsynaptic AMPA receptors, this might involve changes in receptor number/distribution, unitary conductance, kinetics, or glutamate affinity. The observation that GluR2-containing synaptic AMP...

Ionotropic glutamate receptors play important roles in spinal processing of nociceptive sensory signals and induction of central sensitization in chronic pain. Here we applied highly sensitive freeze-fracture replica labeling to laminae I-II of the spinal dorsal horn of rats and investigated the numbers, densities, and colocalization of AMPA- and NMDA-type glutamate receptors at individual post...

This study is aimed at testing the hypothesis that sustained phosphorylation underlies long-term desensitization of AMPA receptors, which is thought to be the mechanism of long-term synaptic depression in cerebellar Purkinje cells (PCs). We induced long-term desensitization of AMPA receptors in rat cerebellar slices by (1) a 4-min bath application of quisqualate (0.1 mM) or (2) a 15-min bath ap...