AMPA-type glutamate receptors (GluRs) play major roles in excitatory synaptic transmission. Neuronal AMPA receptors comprise GluR subunits and transmembrane AMPA receptor regulatory proteins (TARPs). Previous studies identified five mammalian TARPs, gamma-2 (or stargazin), gamma-3, gamma-4, gamma-7, and gamma-8, that enhance AMPA receptor function. Here, we classify gamma-5 as a distinct class ...

The GluA2 subunit in heteromeric alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor channels restricts Ca(2+) permeability and block by polyamines, rendering linear the current-voltage relationship of these glutamate-gated cation channels. Although GluA2-lacking synaptic AMPA receptors occur in GABA-ergic inhibitory neurons, hippocampal CA1 pyramidal cell synapses are wide...

Abstract: The establishment of functional neuronal circuits relies on the formation of excess synapses, followed by the elimination of inappropriate connections. Although the stabilization of presynaptic inputs is critical for the development of functional circuits, the signals that regulate presynaptic stability are not known. Here we report that synapse formation in cortical cultures is highl...

The kinetics of ligand gated ion channels are tuned to permit diverse roles in cellular signaling. To follow high-frequency excitatory synaptic input, postsynaptic AMPA-type glutamate receptors must recover rapidly from desensitization. Chimeras between AMPA and the related kainate receptors demonstrate that the ligand binding domains alone control the lifetime of the desensitized state. Mutati...

Manfridi, Alfredo, Dario Brambilla, and Mauro Mancia. Stimulation of NMDA and AMPA receptors in the rat nucleus basalis of Meynert affects sleep. Am. J. Physiol. 277 (Regulatory Integrative Comp. Physiol. 46): R1488–R1492, 1999.—The nucleus basalis of Meynert (NBM), a heterogeneous area in the basal forebrain involved in the modulation of sleep and wakefulness, is rich in glutamate receptors, a...

AMPA and NMDA receptors are coexpressed at many central synapses, but the factors that control the ratio of these two receptors are not well understood. We recorded mixed miniature or evoked synaptic currents arising from coactivation of AMPA and NMDA receptors and found that long-lasting changes in activity scaled both currents up and down proportionally through changes in the number of postsy...

Glutamate receptors belonging to the AMPA (alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid) subclass were partially purified 30- to 60-fold from forebrain of adult rats and incorporated into planar bimolecular lipid membranes. The channel conductance associated with the reconstituted receptors was activated by kainate and AMPA in a manner that suggests cooperative binding of two to thr...

The synaptic localization, clustering, and immobilization of neurotransmitter receptors and ion channels play important roles in synapse formation and synaptic transmission. Although several proteins have been identified that interact with AMPA receptors and that may regulate their synaptic targeting, little is known about the interaction of AMPA receptors with the cytoskeleton. In studies exam...

Previous studies have suggested that photoreceptor synaptic inputs to depolarizing bipolar cells (DBCs or ON bipolar cells) are mediated by mGluR6 receptors and those to hyperpolarizing bipolar cells (HBCs or OFF bipolar cells) are mediated by AMPA/kainate receptors. Here we show that in addition to mGluR6 receptors which mediate the sign-inverting, depolarizing light responses, subpopulations ...

AMPA receptor-mediated excitotoxicity is proposed to play a major pathogenic role in the selective motoneuron death of amyotrophic lateral sclerosis. Motoneurons have been shown in various models to be more susceptible to AMPA receptor-mediated injury than other spinal neurons. It has been hypothesized that this selective vulnerability of motoneurons is caused by the expression of highly Ca(2+)...