Search results for "aspartate"
showing 10 items of 195 documents
Electrophysiological and Iontophoretic Aspects of the Habenular Influence on Hippocampal Neurones
1995
In previous experimental studies, carried out on cats, we demonstrated that electrical stimulation of lateral habenula (LH) at 0.5-3.0 Hz or 5-20 Hz had a double effect (low frequency-excitation; high frequency-inhibition) on the spontaneous firing rate of single hippocampal neurones. Our results, in agreement with similar case studies, allowed us to hypothesise that in the habenular modulation of the hippocampus the raphe nucleus is probably involved. In fact, all the effects of LH stimulation were antagonised by the iontophoretic intrahippocampal application of methysergide. In the present series of experiments, performed on rats, it was possible to demonstrate that LH stimulation at 1-10…
The effects of nitric oxide on striatal serotoninergic transmission involve multiple targets: an in vivo microdialysis study in the awake rat
2004
Abstract The role of endogenous nitric oxide (NO) in N -methyl- d -aspartate (NMDA)-induced modulation of serotonin (5-HT) release in the striatum of freely moving rats has been studied using microdialysis technique. NMDA-induced increase in 5-HT release was significantly inhibited by selective nitric oxide synthase (nNOS) inhibitor S -methylthiocitrulline (S-Me-TC), ONOO − scavenger l -cysteine ( l -cys), and guanylate cyclase (GC) inhibitor 1 H [1,2,4]oxadiazolo[4,3- a ]quinoxalin-1-one (ODQ). These data suggest that modulation of 5-HT levels is linked to the formation of NO produced by NMDA receptor activation and that endogenously produced NO increases 5-HT concentrations both by stimul…
Safety of etanercept and methotrexate in patients with rheumatoid arthritis and hepatitis C virus infection: a multicenter randomized clinical trial.
2014
Objective.To evaluate the safety and efficacy of therapy with etanercept and methotrexate (MTX) in patients with active rheumatoid arthritis (RA) and mild hepatitis C virus (HCV) infection.Methods.In this prospective open study, 29 patients with active RA were randomly assigned to receive therapy with MTX alone, etanercept alone, or a combination of MTX and etanercept, and monitored up to 54 weeks. The primary endpoint was safety; secondary aims were efficacy as defined by the 44-joint Disease Activity Score (DAS44) and health assessment questionnaire (HAQ). Serum liver enzymes and HCV viral load were serially measured.Results.In the whole cohort, aspartate aminotransferase (AST) serum leve…
Depletion of polysialic acid from neural cell adhesion molecule (PSA-NCAM) increases CA3 dendritic arborization and increases vulnerability to excito…
2012
Chronic immobilization stress (CIS) shortens apical dendritic trees of CA3 pyramidal neurons in the hippocampus of the male rat, and dendritic length may be a determinant of vulnerability to stress. Expression of the polysialylated form of neural cell adhesion molecule (PSA-NCAM) in the hippocampal formation is increased by stress, while PSA removal by Endo-neuraminidase-N (endo-N) is known to cause the mossy fibers to defasciculate and synapse ectopically in their CA3 target area. We show here that enzymatic removal of PSA produced a remarkable expansion of dendritic arbors of CA3 pyramidal neurons, with a lesser effect in CA1. This expansion eclipsed the CIS-induced shortening of CA3 dend…
Differential effect of beta-N-oxalylamino-L-alanine, the Lathyrus sativus neurotoxin, and (+/-)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate …
2000
We studied the effect of beta-oxalylamino-L-alanine, a glutamate analog present in Lathyrus sativus seeds and implicated in the etiopathogenesis of neurolathyrism, and (+/-)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionate on the extracellular levels of aspartate, glutamate and taurine in the primary motor cortex of freely moving rats. We found that while both neurotoxins increase the level of aspartate and glutamate, only (+/-)-alpha(-amino-3-hydroxy-5-methylisoxazole-4-propionate is able to modulate the level of taurine. GYKI-52466, a non-competitive non-NMDA antagonist, inhibited beta-oxalylamino-L-alanine-induced increase of aspartate, but not that of glutamate. Conversely, this ant…
Xenon Improves Neurologic Outcome and Reduces Secondary Injury Following Trauma in an In Vivo Model of Traumatic Brain Injury*
2014
Objectives: To determine the neuroprotective efficacy of the inert gas xenon following traumatic brain injury and to determine whether application of xenon has a clinically relevant therapeutic time window. Design: Controlled animal study. Setting: University research laboratory. Subjects: Male C57BL/6N mice (n = 196). Interventions: Seventy-five percent xenon, 50% xenon, or 30% xenon, with 25% oxygen (balance nitrogen) treatment following mechanical brain lesion by controlled cortical impact. Measurements and Main Results: Outcome following trauma was measured using 1) functional neurologic outcome score, 2) histological measurement of contusion volume, and 3) analysis of locomotor functio…
Xenon improves long-term cognitive function, reduces neuronal loss and chronic neuroinflammation, and improves survival after traumatic brain injury …
2019
Background.Xenon is a noble gas with neuroprotective properties. We previously showed that xenon improves short and long-term outcomes in young adult mice after controlled cortical impact (CCI). This is a follow-up study investigating xenon’s effect on very long-term outcome and survival. Methods.C57BL/6N (n=72) young adult male mice received single CCI or sham surgery and were treated with either xenon (75%Xe:25%O2) or control gas (75% N2:25%O2). The outcomes used were: 1) 24-hour lesion volume and neurological outcome score; 2)contextual fear-conditioning at 2 weeks and 20 months; 3) corpus callosum white matter quantification; 4) immunohistological assessment of neuroinflammation and neu…
Role of NMDA and AMPA glutamatergic receptors in the effects of social defeat on the rewarding properties of MDMA in mice
2019
Exposure to social stress alters the response to drugs of abuse of experimental animals. Changes in the glutamatergic system seem to play a role in the effects of social defeat stress on the rewarding properties of cocaine and amphetamine. The aim of the present study was to evaluate the involvement of N-methyl-D-aspartate (NMDA) and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) glutamate receptors in the effects of social defeat on the conditioned place preference induced by 3,4-methylenedioxymethamphetamine (MDMA). Our hypothesis was that changes in these receptors could mediate the effects of social defeat on MDMA reward. Young adult male mice were exposed to an episode…
Behavioural parameters in aged rats are related to LTP and gene expression of ChAT and NMDA-NR2 subunits in the striatum.
2004
Striatal parameters were assessed for their relevance to age-related behavioural decline. Forty aged rats (28-30 months) were tested in the water maze and open field. Of these, seven superior and seven inferior learners were compared with each other in terms of levels of in vitro short- and long-term potentiation (STP and LTP), and gene expression of choline acetyltransferase (ChAT) as well as of the NMDA-NR2A-C subunits assessed by quantitative RT-PCR. Results revealed that the superior as compared with the inferior learners had higher levels of ChAT mRNA in the striatum. For the superior group, ChAT mRNA was correlated with escape on to the cued platform in the water maze, whereas level o…
Percutaneous antegrade electropapillotomy. Study in dogs.
1984
Antegrade electropapillotomy using the percutaneous transcystic approach was successfully performed in 11 of 16 dogs. When the intervention was effective, the pressure gradient between common bile duct and duodenum decreased from 6 to 1.3 mm Hg on average and returned to gradients slightly below the initial values after 4 weeks, owing to reactivation of the sphincter mechanism. Ineffective cutting, however, resulted in a temporary pressure rise. In one dog a papillary stenosis developed and was relieved by antegrade electrocutting. Irrespective of the success of the papillotomy, rises in levels of serum glutamine oxaloacetic and pyruvic transaminase, alkaline phosphatase, serum amylase and …