Eriksson-Grennberg, Kerstin G. (University of Uppsala, Uppsala, Sweden), Hans G. Boman, J. A. Torbjörn Jansson, and Sone Thorén. Resistance of Escherichia coli to penicillins. I. Genetic study of some ampicillin-resistant mutants. J. Bacteriol. 90:54-62. 1965.-A number of ampicillin-resistant mutants have been isolated and characterized. Of these strains, two groups have been genetically invest...

Most excitatory synaptic transmissions in the central nervous system are mediated by the neurotransmitter glutamate. Binding of glutamate released from the presynaptic membrane causes glutamate receptors in the postsynaptic membrane to open, which results in a transient depolarization of the postsynaptic membrane. The AMPA (alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid) subtype of g...

The importance of AMPA-type glutamate receptors has been demonstrated in neuronal plasticity and in adaptation to drugs of abuse. We studied the involvement of AMPA receptors in social interaction and anxiety and found that in several paradigms of agonistic behavior naïve male mice deficient for the GluR-A subunit- containing AMPA receptors are less aggressive than wild-type littermates. GluR-A...

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...

The transmembrane protein stargazin enhances levels of functional AMPA receptors at the neuronal plasma membrane and at synapses. To clarify the mechanism for this effect, we studied trafficking of the AMPA receptor subunit glutamate receptor 1 (GluR1) in transfected COS7 cells. GluR1 expressed poorly on the surface of these cells and was primarily retained in the endoplasmic reticulum (ER). St...

We report that a novel sulfonylamino compound, 4-[2-(phenylsulfonylamino)ethylthio]-2,6-difluoro-phenoxyacetam ide (PEPA), selectively potentiates glutamate receptors of the AMPA subtype. PEPA (1-200 microM) dose dependently potentiated glutamate-evoked currents in Xenopus oocytes expressing AMPA (GluRA-GluRD), but not kainate (GluR6 and GluR6+KA2) or NMDA (zeta1 + epsilon1-epsilon4), receptor ...

AIMS To investigate glutamate receptor subtypes during alcohol withdrawal. METHODS Rats were exposed to severe alcohol intoxication for 84 h and then decapitated at 0, 12 and 36 h after the last alcohol dose (n = 7 per group). Alcohol was administered five times a day by intragastric intubation. The densities of N-methyl-D-aspartate (NMDA) and 2-amino-3-hydroxy-5-methyl-4-isoxazolepropionic a...

AMPA receptor-mediated excitotoxicity has been implicated in the selective degeneration of motor neurons in amyotrophic lateral sclerosis (ALS). Motor neurons in vitro are particularly vulnerable to excessive AMPA receptor stimulation and one of the factors underlying this selective vulnerability is the presence of a large proportion of Ca2+ -permeable (i.e. GluR2-lacking) AMPA receptors. Howev...

Amacrine cells are thought to be a major locus for mechanisms of light adaptation and contrast enhancement in the retina. However, the potential for plasticity in their AMPA receptor currents remains largely unknown. Using paired patch-clamp recordings between bipolar cell terminals and amacrine cells, we have simultaneously measured presynaptic membrane capacitance changes and EPSCs. Repetitiv...

AMPA-type glutamate receptors (AMPA-Rs) mediate a majority of excitatory synaptic transmission in the brain. In hippocampus, most AMPA-Rs are hetero-oligomers composed of GluR1/GluR2 or GluR2/GluR3 subunits. Here we show that these AMPA-R forms display different synaptic delivery mechanisms. GluR1/GluR2 receptors are added to synapses during plasticity; this requires interactions between GluR1 ...