Journal: Proceedings of the National Academy of Sciences of the United States of America

Article Title: Protection from fatal viral encephalomyelitis: AMPA receptor antagonists have a direct effect on the inflammatory response to infection

doi: 10.1073/pnas.0712390105

Figure Lengend Snippet: Morbidity and mortality of untreated and talampanel-treated, NSV-infected mice. B6 mice infected intracerebrally with 103 pfu of NSV received either 15 mg/kg talampanel (n = 20) or vehicle (n = 20) every 12 h for 8 days after infection. (A) Paralysis in untreated (NSV) and treated (NSV+Tal) groups. Paralysis scoring was as follows: 0, no signs of illness; 1, weakness; 2, moderate paralysis in one hindlimb; 3, severe paralysis in both hind limbs; and 4, death. The data represent means ± SD. P = 0.0276, unpaired Student's t test. (B) Mortality in untreated and treated mice. P = 0.0002, Kaplan–Meier log rank test.

Article Snippet: The AMPA glutamate receptor antagonist talampanel (IVAX Research) was dissolved in DMSO.

Techniques: Infection

Journal: Proceedings of the National Academy of Sciences of the United States of America

Article Title: Protection from fatal viral encephalomyelitis: AMPA receptor antagonists have a direct effect on the inflammatory response to infection

doi: 10.1073/pnas.0712390105

Figure Lengend Snippet: Effect of talampanel treatment on virus replication. (A) Differentiated CSM 14.1 cells were infected with NSV at an multiplicity of infection of 10 and treated with 0.1 or 1 μM talampanel either 1 h before infection (PT) or immediately after infection. Supernatant fluids were assayed for infectious virus by plaque formation. (B and C) B6 mice were infected with 1,000 pfu of NSV intracerebrally and treated with 15 mg/kg talampanel twice daily (NSV+Tal) or not treated (NSV). Tissue homogenates from brain (B) and spinal cord (C) were assayed for infectious virus. The bars represent geometric means ± SD of three samples per group. The line indicates the limit of detection. ***, P < 0.0009; ****, P < 0.0001.

Article Snippet: The AMPA glutamate receptor antagonist talampanel (IVAX Research) was dissolved in DMSO.

Techniques: Virus, Infection

Journal: Proceedings of the National Academy of Sciences of the United States of America

Article Title: Protection from fatal viral encephalomyelitis: AMPA receptor antagonists have a direct effect on the inflammatory response to infection

doi: 10.1073/pnas.0712390105

Figure Lengend Snippet: NSV protein in the brains of untreated and talampanel-treated, NSV-infected mice. (A and B) Paraffin-embedded sections from the brains of untreated (A) and talampanel-treated (B) mice 7 days after intracerebral infection with NSV were stained with antibody to SINV. (C) Quantitative analysis of numbers of NSV-positive cells. The bars represent means ± SD of positive cells per unit area (0.986 mm2) for 20 areas per animal for three animals per group. ***, P = 0.0006.

Article Snippet: The AMPA glutamate receptor antagonist talampanel (IVAX Research) was dissolved in DMSO.

Techniques: Infection, Staining

Journal: Proceedings of the National Academy of Sciences of the United States of America

Article Title: Protection from fatal viral encephalomyelitis: AMPA receptor antagonists have a direct effect on the inflammatory response to infection

doi: 10.1073/pnas.0712390105

Figure Lengend Snippet: Histological and immunohistochemical examination of untreated and talampanel-treated, NSV-infected mice. (A–H) Paraffin-embedded sections of brain from untreated (NSV) and talampanel-treated (NSV+Tal) mice were stained with H&E (day 7) (A and B) or antibodies to CD45 (day 5) (C and D), CD3 (day 7) (E and F), and GFAP (day 5) (G and H). (I and J) Numbers of infiltrating CD45+ cells (I) and CD3+ cells (J) were quantitated for 20 areas (0.986 mm2) per animal for three animals per group. **, P < 0.01; ***, P < 0.001; ****, P < 0.0001.

Article Snippet: The AMPA glutamate receptor antagonist talampanel (IVAX Research) was dissolved in DMSO.

Techniques: Immunohistochemical staining, Infection, Staining

Journal: Proceedings of the National Academy of Sciences of the United States of America

Article Title: Protection from fatal viral encephalomyelitis: AMPA receptor antagonists have a direct effect on the inflammatory response to infection

doi: 10.1073/pnas.0712390105

Figure Lengend Snippet: GFAP promoter activation in untreated and talampanel-treated, NSV-infected GFAP–luciferase FVB/n mice. Transgenic mice expressing luciferase behind the GFAP promoter were mock-infected (PBS) or infected with NSV and not treated (NSV) or infected and treated with talampanel (NSV+Tal). For 10 days after infection, three mice per group were injected with luciferin and imaged. (A) Representative images from one mouse per group on days 2, 4, 6, 8, and 10. (B) Quantitation of light/pixel of mock-infected (PBS), untreated (NSV), and treated (NSV+Tal) mice. The bars represent means ± SEM for three animals per group per day. *, P = 0.0257; **, P < 0.01. (C) Results of immunoblot analysis of GFAP expression in brains of untreated and treated B6 mice from three independent experiments. The points represent the means ± SEM of three mice per group. **, P < 0.01.

Article Snippet: The AMPA glutamate receptor antagonist talampanel (IVAX Research) was dissolved in DMSO.

Techniques: Activation Assay, Infection, Luciferase, Transgenic Assay, Expressing, Injection, Quantitation Assay, Western Blot

Journal: Proceedings of the National Academy of Sciences of the United States of America

Article Title: Protection from fatal viral encephalomyelitis: AMPA receptor antagonists have a direct effect on the inflammatory response to infection

doi: 10.1073/pnas.0712390105

Figure Lengend Snippet: Immune responses in untreated and talampanel-treated, NSV-infected mice. (A and B) Draining cervical and deep cervical lymph nodes were collected and weighed (A), and cells were counted (B). (C and D) Cells were analyzed by flow cytometry for expression of CD4 (C) and CD8 (D) on CD3+ cells. (E and F) Sera were assayed for NSV-specific neutralizing antibody by PRNT (E) and for binding IgG antibody by EIA (F). The points represent means ± SEM of three samples per group. *, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001.

Article Snippet: The AMPA glutamate receptor antagonist talampanel (IVAX Research) was dissolved in DMSO.

Techniques: Infection, Flow Cytometry, Expressing, Binding Assay

Journal: The Journal of Neuroscience

Article Title: Developmental Increase in Vesicular Glutamate Content Does Not Cause Saturation of AMPA Receptors at the Calyx of Held Synapse

doi: 10.1523/JNEUROSCI.23-09-03633.2003

Figure Lengend Snippet: Single-channel conductance of AMPA receptors underlying mEPSCs. Right column, Individual mEPSCs (top) (10 records superimposed after peak alignment) and averaged mEPSCs (bottom) at P6, P14, and P28. Left column, Peak-scaled variance-mean current plots obtained by the nonstationary fluctuation analysis for mEPSCs in P6, P14, and P28 rats. These ς2–I plots were calculated from 162, 341, and 371 events, respectively. Mean single-channel current was estimated from the initial slope of the ς2–I relationships. To estimate single-channel conductance (γ), reversal potentials of mEPSCs were measured in each recording.

Article Snippet: Whereas the former possibility is technically difficult to assess, we examined the latter possibility by testing the effect of the rapidly dissociating AMPA receptor antagonist kynurenate on mEPSCs ( Diamond and Jahr, 1997 ; Wadiche and Jahr, 2001 ).

Techniques:

Journal: The Journal of Neuroscience

Article Title: Developmental Increase in Vesicular Glutamate Content Does Not Cause Saturation of AMPA Receptors at the Calyx of Held Synapse

doi: 10.1523/JNEUROSCI.23-09-03633.2003

Figure Lengend Snippet: Developmental increase in the quantal transmitter concentration in the synaptic cleft detected by the low-affinity AMPA receptor antagonist kynurenate (KYN) (50 μm).A, Sample records (averaged from 243 events for each) and amplitude histograms of mEPSCs recorded from an MNTB neuron, before (thin line) and after (thick line) application of kynurenate (superimposed), each at P14, P29, and P14 with 50 mml-glutamate (50Glu) loaded into a calyceal terminal. Filled bars are background noise histograms.B, C, Mean amplitude of mEPSCs (B) and their percentage inhibition by kynurenate (C) at P13–P14, P28–P29, and P13–P14 with 50 mml-glutamate loaded into calyceal terminals. Asterisks indicate a significant difference withp < 0.01 (Sheffe test).

Article Snippet: Whereas the former possibility is technically difficult to assess, we examined the latter possibility by testing the effect of the rapidly dissociating AMPA receptor antagonist kynurenate on mEPSCs ( Diamond and Jahr, 1997 ; Wadiche and Jahr, 2001 ).

Techniques: Concentration Assay, Inhibition

Journal: The Journal of Neuroscience

Article Title: Developmental Increase in Vesicular Glutamate Content Does Not Cause Saturation of AMPA Receptors at the Calyx of Held Synapse

doi: 10.1523/JNEUROSCI.23-09-03633.2003

Figure Lengend Snippet: Nonsaturation of postsynaptic AMPA receptors at mature synapses. A, Miniature EPSCs recorded from a P28 MNTB neuron before (i) and after (ii) loading 100 mml-glutamate into a calyceal terminal. Each data point represents the mean amplitude of mEPSCs sampled every 20 sec. Sample records of mEPSCs before (i) and after (ii) thel-glutamate loading at a slow sweep (top) and a fast sweep (bottom left, superimposed), and those normalized in the amplitude (bottom right, superimposed). B, Amplitude histograms of mEPSCs recorded from the same neuron before (i) and after (ii) thel-glutamate loading (number of events is 427 and 420, respectively). C, Summary data of mEPSCs from four synapses at P28–P29. The mean amplitude of mEPSCs before thel-glutamate loading was 54.3 ± 5.4 pA.D, Potentiation of evoked EPSCs by presynaptic loading of l-glutamate in a P29 rat. Sample records are averaged presynaptic action potentials (top, superimposed) and EPSCs before (i) and after (ii) the l-glutamate loading (bottom, superimposed). E, Summary data for evoked EPSCs (open circles) and spontaneous EPSCs (filled circles) from four synapses at P29. Before l-glutamate loading, the mean amplitude of evoked EPSCs was 4.37 ± 0.71 nA, and that of spontaneous EPSCs was 64.0 ± 10.6 pA. Glu, Glutamate. Dotted lines in Cand E denote mean values of data points beforel-glutamate loadings.

Article Snippet: Whereas the former possibility is technically difficult to assess, we examined the latter possibility by testing the effect of the rapidly dissociating AMPA receptor antagonist kynurenate on mEPSCs ( Diamond and Jahr, 1997 ; Wadiche and Jahr, 2001 ).

Techniques:

Journal: The Journal of neuroscience : the official journal of the Society for Neuroscience

Article Title: A target-cell specific role for presynaptic Fmr1 in regulating glutamate release onto neocortical fast-spiking inhibitory neurons

doi: 10.1523/JNEUROSCI.2447-12.2013

Figure Lengend Snippet: The presynaptic Fmr1 deletion phenotype can be mimicked with a decrease in release probability in presynaptic WT pairs. (A) Left: Example average traces before and after 4 μM CdCl2. Right: We obtained the relationship between CdCl2 (Cd+2) concentration and blockade of uEPSC1. Data were fitted to a sigmoid curve. Dashed lines mark the [Cd+2] (2.6 μM) that corresponds to the average fractional decrease of uEPSC1 amplitude found for presynaptic Fmr1 deletion (0.40). (B) Example average traces obtained from a WT/WT pair in the presence of 2.6 μM CdCl2 before and after kynurenate (Kyn, 250 μM) application. (C) Average blockade by kynurenate with 2.6 μM CdCl2 closely matched the blockade for presynaptic KO pairs. (D) No change in short-term plasticity with Cd2+ application. WT/WT and KO/WT data in C and D are replotted from fig. 5. * p < 0.05. Scale bars in A and B: 20 pA, 2 ms.

Article Snippet: Changes in transient glutamate concentration and receptor saturation at individual synapses are assayed by the amount of blockade of the EPSC by a low-affinity competitive AMPA receptor (AMPAR) antagonist, such as kynurenate ( Wadiche and Jahr, 2001 ).

Techniques: Concentration Assay

Journal: The Journal of neuroscience : the official journal of the Society for Neuroscience

Article Title: A target-cell specific role for presynaptic Fmr1 in regulating glutamate release onto neocortical fast-spiking inhibitory neurons

doi: 10.1523/JNEUROSCI.2447-12.2013

Figure Lengend Snippet: Presynaptic Fmr1 deletion causes reduced multivesicular release. (A) Example average traces obtained from a WT/WT pair demonstrating the effect of the AMPAR competitive antagonist, kynurenate (Kyn, 250 μM). Note the greater blockade of uEPSC2 compared to blockade of uEPSC1, indicating multivesicular release. Scale bars: 20 pA, 2 ms. (B) Paired line plots showing Kyn blockade for uEPSC1 and uEPSC2 with presynaptic WT (left) and presynaptic KO expression (right). Dark lines indicate average data. (C) Paired line plots showing blockade by the noncompetitive AMPAR antagonist, NBQX (75 nM). NBQX had uniform affects across uEPSC number. (D) Blockade by Kyn of uEPSC1 was greater with presynaptic KO, indicating less multivesicular release. (E) Blockade by NBQX of uEPSC1 was not different with presynaptic KO. (F) No change in short-term plasticity as observed by the average normalized uEPSC amplitude during the paired pulse train. * p < 0.05,** p < 0.01.

Article Snippet: Changes in transient glutamate concentration and receptor saturation at individual synapses are assayed by the amount of blockade of the EPSC by a low-affinity competitive AMPA receptor (AMPAR) antagonist, such as kynurenate ( Wadiche and Jahr, 2001 ).

Techniques: Expressing

Journal: The Journal of neuroscience : the official journal of the Society for Neuroscience

Article Title: A target-cell specific role for presynaptic Fmr1 in regulating glutamate release onto neocortical fast-spiking inhibitory neurons

doi: 10.1523/JNEUROSCI.2447-12.2013

Figure Lengend Snippet: The presynaptic Fmr1 deletion phenotype can be rescued with an increase in release probability in presynaptic KO pairs. (A) Left: Example average traces before and after 6 mM CaCl2. Right: We obtained the relationship between CaCl2 (Ca+2) concentration and increase of uEPSC1 amplitude. Data were fitted to a sigmoid curve. Dashed lines mark the [Ca+2] (6 mM) that corresponds to the average fractional increase of uEPSC1 amplitude found for WT/WT pairs over KO/WT pairs (0.62). (B) Example average traces obtained from a KO/WT pair in the presence of 6 mM CaCl2 before and after kynurenate (250 μM) application. (C) Average blockade by kynurenate with 6mM CaCl2 closely matched the blockade for presynaptic WT pairs. (D) More short-term depression in high Ca2+. KO/WT and WT/WT data in C and D are replotted from fig. 5. * p < 0.05. Scale bars in A and B: 20 pA, 2 ms.

Article Snippet: Changes in transient glutamate concentration and receptor saturation at individual synapses are assayed by the amount of blockade of the EPSC by a low-affinity competitive AMPA receptor (AMPAR) antagonist, such as kynurenate ( Wadiche and Jahr, 2001 ).

Techniques: Concentration Assay