Consulta: subjectFacets:"Glutamate"
Registros recuperados: 19
Data/hora: 10/06/2024 17:17:08

Simultaneous environmental manipulations in semi-perfusion cultures of CHO cells producing rh-tPA
Provedor de dados: Electronic Journal of Biotechnology
Autores: Vergara,Mauricio; Becerra,Silvana; Díaz-Barrera,Alvaro; Berrios,Julio; Altamirano,Claudia.
We evaluated the combined effect of decreasing the temperature to a mild hypothermia range (34 and 31ºC) and switching to a slowly metabolizable carbon source (glucose substituted by galactose) on the growth and production of a recombinant human tissue plasminogen activator (rh-tPA) by Chinese hamster ovary cells in batch and semi-perfusion cultures. In batch cultures using glucose as a carbon source, decreasing the temperature caused a reduction in cell growth and an increase in specific productivity of rh-tPA of 32% at 34ºC and 55% at 31ºC, compared to cultures at 37ºC. Similar behaviour was observed in cultures at 34ºC using galactose as a carbon source. Nonetheless, at 31ºC, the specific productivity of rh-tPA strongly decreased (about 58%) compared to...
Tipo: Journal article
Palavras-chave: CHO cells; Galactose; Glutamate; Low temperature; Perfusion culture; Rh-tPA.
Ano: 2012
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582012000600002

In silico analysis of binding interaction of conantokins with NMDA receptors for potential therapeutic use in Alzheimer’s disease
Provedor de dados: Journal of Venomous Animals and Toxins Including Tropical Diseases
Autores: Batool,Maleeha Waqar and Sidra.
Abstract  Background  The N-methyl-D-aspartate (NMDA) receptors are glutamate receptors that play vital roles in central nervous system development and are involved in synaptic plasticity, which is an essential process for learning and memory. The subunit N-methyl D-aspartate receptor subtype 2B (NR2B) is the chief excitatory neurotransmitter receptor in the mammalian brain. Disturbances in the neurotransmission mediated by the NMDA receptor are caused by its overexposure to glutamate neurotransmitter and can be treated by its binding to an antagonist. Among several antagonists, conantokins from cone snails are reported to bind to NMDA receptors.  Methods  This study was designed to analyze the binding mode of conantokins with NMDA receptors in both humans...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: N-methyl-D-aspartate; Glutamate; Synaptic plasticity; NR2B; Neurotransmitter; Antagonists; Conantokins; Docking; In silico; Alzheimer’s dieases.
Ano: 2017
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992017000100317

Antinociceptive effect of PnTx4(5-5), a peptide from Phoneutria nigriventer spider venom, in rat models and the involvement of glutamatergic system
Provedor de dados: Journal of Venomous Animals and Toxins Including Tropical Diseases
Autores: Oliveira,Camila Franco Batista; Alves,Daniela Pereira; Emerich,Bruna Luiza; Figueiredo,Suely Gomes de; Cordeiro,Marta do Nascimento; Borges,Márcia Helena; Richardson,Michael; Pimenta,Adriano Monteiro de Castro; Duarte,Igor Dimitri Gama; Lima,Maria Elena de.
ABSTRACT  Background:  The venom of Phoneutria nigriventer spider is a source of numerous bioactive substances, including some toxins active in insects. An example is PnTx4(5-5) that shows a high insecticidal activity and no apparent toxicity to mice, although it inhibited NMDA-evoked currents in rat hippocampal neurons. In this work the analgesic activity of PnTx4(5-5) (renamed Γ-ctenitoxin-Pn1a) was investigated.  Methods:  The antinociceptive activity was evaluated using the paw pressure test in rats, after hyperalgesia induction with intraplantar injection of carrageenan or prostaglandin E2 (PGE2).  Results:  PnTx4(5-5), subcutaneously injected, was able to reduce the hyperalgesia induced by PGE2 in rat paw, demonstrating a systemic effect. PnTx4(5-5)...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Spider toxin; Γ-ctenitoxin-Pn1a; PnTx4(5-5); Phoneutria nigriventer; Antinociception; Glutamate.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1678-91992019000100316

Differences in ureide and amino acid content of water stressed soybean inoculated with Bradyrhizobium japonicum and B. elkanii
Provedor de dados: Pesquisa Agropecuária Brasileira
Autores: Ramos,Maria Lucrecia Gerosa; Parsons,Richard; Sprent,Janet Irene.
The objective of this work was to study the response to water stress of a drought sensitive soybean cultivar inoculated with Bradyrhizobium japonicum (strain CB1809, Semia 586) and B. elkanii (strain 29W, Semia 5019). CB1809 nodulated plants produced a significantly higher root fraction (19%) than 29W (14.6%). Plants inoculated with CB1809 produced less nodules and accumulated more nitrogen than those inoculated with 29W. In general, low amounts of ureides in nodules were found in watered plants inoculated with either CB1809 or 29W strains, but those levels were five-fold increased in stressed plants inoculated with CB1809. Nodules formed by strain CB1809 had aspartate and glutamate as major amino acids, while those formed by 29W had glutamate, asparagine...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Glycine max; Alanine; Asparagine; Aspartate; Glutamate; Nitrogen fixation.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2005000500005

CRF1/CRF2 and MC3/MC4 Receptors Affect Glutamate- Induced Food Intake in Neonatal Meat-Type Chicken
Provedor de dados: Revista Brasileira de Ciência Avícola
Autores: Ahmadi,F; Zendehdel,M; Babapour,V; Panahi,N.
ABSTRACT Central glutamate, melanocortin and corticotropin systems have mediatory role on several physiologic functions in the brain, but their interactions on appetite regulation are not fully elicited. So, the aim of the current study was to determine interaction of the glutamate with melanocortin and corticotropin systems on food intake in 3-h food-deprived (FD3) neonatal meat-type chicken. In experiment 1, chicken intracerebroventricular (ICV) injected (A) phosphate-buffered saline (PBS), (B) glutamate (75 nmol), (C) glutamate (150 nmol) and (D) glutamate (300 nmol). In experiment 2, (A) PBS, (B) astressin-B (CRF1/CRF2 receptors antagonist, 30 µg), (C) glutamate (300 nmol) and (D) astressin-B+glutamate were ICV injected. Experiments 3-5 were similar to...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Glutamate; Melanocortin; Corticotrophin; Food intake; Neonatal chicken.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-635X2019000100322

Distribution of AMPA-type glutamate receptor subunits in the chick visual system
Provedor de dados: Brazilian Journal of Medical and Biological Research
Several glutamate receptor (GluR) subunits have been characterized during the past few years. In the present study, subunit-specific antisera were used to determine the distribution of the AMPA-type glutamate receptor subunits GluR1-4 in retinorecipient areas of the chick brain. Six white leghorn chicks (Gallus gallus, 7-15 days old, unknown sex) were deeply anesthetized and perfused with 4% buffered paraformaldehyde and brain sections were stained using immunoperoxidase techniques. The AMPA-type glutamate receptor subunits GluR1, GluR2/3 and GluR4 were present in several retinorecipient areas, with varying degrees of colocalization. For example, perikarya in layers 2, 3, and 5 of the optic tectum contained GluR1, whereas GluR2/3 subunits appeared mainly...
Palavras-chave: Glutamate; Receptors; Neurotransmitters; Visual system; Visual pathways.
Ano: 1997
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1997000100012

Glutamine and glutamate as vital metabolites
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Newsholme,P.; Lima,M.M.R.; Procopio,J.; Pithon-Curi,T.C.; Doi,S.Q.; Bazotte,R.B.; Curi,R.
Glucose is widely accepted as the primary nutrient for the maintenance and promotion of cell function. This metabolite leads to production of ATP, NADPH and precursors for the synthesis of macromolecules such as nucleic acids and phospholipids. We propose that, in addition to glucose, the 5-carbon amino acids glutamine and glutamate should be considered to be equally important for maintenance and promotion of cell function. The functions of glutamine/glutamate are many, i.e., they are substrates for protein synthesis, anabolic precursors for muscle growth, they regulate acid-base balance in the kidney, they are substrates for ureagenesis in the liver and for hepatic and renal gluconeogenesis, they act as an oxidative fuel for the intestine and cells of the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Glutamine; Glutamate; Glucose; Metabolism; Cell function.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2003000200002

Possible etiologies for tropical spastic paraparesis and human T lymphotropic virus I-associated myelopathy
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Zaninovic',V.
The epidemiology of tropical spastic paraparesis/human T lymphotropic virus I (HTLV-I)-associated myelopathy (TSP/HAM) is frequently inconsistent and suggests environmental factors in the etiology of these syndromes. The neuropathology corresponds to a toxometabolic or autoimmune process and possibly not to a viral disease. Some logical hypotheses about the etiology and physiopathology of TSP and HAM are proposed. Glutamate-mediated excitotoxicity, central distal axonopathies, cassava, lathyrism and cycad toxicity may explain most cases of TSP. The damage caused to astrocytes and to the blood-brain barrier by HTLV-I plus xenobiotics may explain most cases of HAM. Analysis of the HTLV-I/xenobiotic ratio clarifies most of the paradoxical epidemiology of TSP...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: TSP/HAM; Paradoxical epidemiology; Toxic and toxoviral etiologies; HTLV-I; Glutamate; Astrocytes; Cycads; Cassava.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2004000100001

Localization of NMDA receptors in the cerebral cortex: a schematic overview
Provedor de dados: Brazilian Journal of Medical and Biological Research
The fundamental role of N-methyl-D-aspartate (NMDA) receptors in many cortical functions has been firmly defined, as has its involvement in a number of neurological and psychiatric diseases. However, until recently very little was known about the anatomical localization of NMDA receptors in the cerebral cortex of mammals. The recent application of molecular biological techniques to the study of NMDA receptors has provided specific tools which have greatly expanded our understanding of the localization of NMDA receptors in the cerebral cortex. In particular, immunocytochemical studies on the distribution of cortical NMDA receptors have shown that NMDA receptors are preferentially localized on dendritic spines, have disclosed an unknown fraction of...
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Glutamate; Ionotropic receptors; Autoreceptors; Heteroreceptors; Astrocytes; Neuron-glia signaling.
Ano: 1997
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1997000500001

ERKs and mitochondria-related pathways are essential for glycyrrhizic acid-mediated neuroprotection against glutamate-induced toxicity in differentiated PC12 cells
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Wang,D.; Guo,T.Q.; Wang,Z.Y.; Lu,J.H.; Liu,D.P.; Meng,Q.F.; Xie,J.; Zhang,X.L.; Liu,Y.; Teng,L.S.
The present study focuses on the neuroprotective effect of glycyrrhizic acid (GA, a major compound separated from Glycyrrhiza Radix, which is a crude Chinese traditional drug) against glutamate-induced cytotoxicity in differentiated PC12 (DPC12) cells. The results showed that GA treatment improved cell viability and ameliorated abnormal glutamate-induced alterations in mitochondria in DPC12 cells. GA reversed glutamate-suppressed B-cell lymphoma 2 levels, inhibited glutamate-enhanced expressions of Bax and cleaved caspase 3, and reduced cytochrome C (Cyto C) release. Exposure to glutamate strongly inhibited phosphorylation of AKT (protein kinase B) and extracellular signal-regulated kinases (ERKs); however, GA pretreatment enhanced activation of ERKs but...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Glycyrrhizic acid; Neuroprotection; Glutamate; ERKs; Mitochondria.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2014000900773

Glutamatergic transmission in the nucleus tractus solitarii: from server to peripherals in the cardiovascular information superhighway
Provedor de dados: Brazilian Journal of Medical and Biological Research
Afferent nerves carrying signals from mechanoreceptors in the aortic arch and carotid sinus terminate predominantly in the nucleus tractus solitarii (NTS). Signal transduction and neurotransmission in the NTS are critical for central cardiovascular reflex control, but little was known about either until the late 1970's. None of the numerous neuroactive chemicals found in the NTS had met strict criteria as a neurotransmitter in the baroreflex arc until data suggested that the excitatory amino acid L-glutamate (GLU) might be released from baroreceptor afferent terminals in the NTS. In anesthetized animals microinjection into the NTS of GLU, which can be demonstrated in terminals in the NTS, produces cardiovascular responses like those seen with activation of...
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Glutamate; Nucleus tractus solitarii; Baroreceptor reflex; Cardiovascular; Vagus; Mechanoreceptors.
Ano: 1997
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X1997000100001

Central actions of glucocorticoids in the control of body fluid homeostasis: Review
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Ruginsk,S.G.; Lopes da Silva,A.; Ventura,R.R.; Elias,L.L.K.; Antunes-Rodrigues,J.
The involvement of the hypothalamic-pituitary-adrenal axis in the control of body fluid homeostasis has been extensively investigated in the past few years. In the present study, we reviewed the recent results obtained using different approaches to investigate the effects of glucocorticoids on the mechanisms of oxytocin and vasopressin synthesis and secretion in response to acute and chronic plasma volume and osmolality changes. The data presented here suggest that glucocorticoids are not only involved in the mechanisms underlying the fast release but also in the transcriptional events that lead to decreased synthesis and secretion of these neuropeptides, particularly oxytocin, under diverse experimental conditions of altered fluid volume and tonicity. The...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Corticosterone; Vasopressin; Oxytocin; Endocannabinoid; Glutamate; NFκB.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2009000100010

Differentiation of autonomic reflex control begins with cellular mechanisms at the first synapse within the nucleus tractus solitarius
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Andresen,M.C.; Doyle,M.W.; Bailey,T.W.; Jin,Y.-H.
Visceral afferents send information via cranial nerves to the nucleus tractus solitarius (NTS). The NTS is the initial step of information processing that culminates in homeostatic reflex responses. Recent evidence suggests that strong afferent synaptic responses in the NTS are most often modulated by depression and this forms a basic principle of central integration of these autonomic pathways. The visceral afferent synapse is uncommonly powerful at the NTS with large unitary response amplitudes and depression rather than facilitation at moderate to high frequencies of activation. Substantial signal depression occurs through multiple mechanisms at this very first brainstem synapse onto second order NTS neurons. This review highlights new approaches to the...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Sensory; Vanilloid; Glutamate; Presynaptic modulation; Autonomic; Visceral; Potassium currents.
Ano: 2004
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2004000400012

Role of the caudal pressor area in the regulation of sympathetic vasomotor tone
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Campos,R.R.; Carillo,B.A.; Oliveira-Sales,E.B.; Silva,A.M.; Silva,N.F.; Futuro Neto,H.A.; Bergamaschi,C.T.
It is well known that the ventrolateral medulla contains neurons involved in the tonic and reflex control of the cardiovascular system. Two regions within the ventrolateral medulla were initially identified: the rostral ventrolateral medulla (RVLM) and the caudal ventrolateral medulla (CVLM). Activation of the RVLM raises arterial blood pressure and sympathetic nerve activity, and activation of the CVLM causes opposite effects. The RVLM premotor neurons project directly to sympathetic preganglionic neurons and are involved in the maintenance of resting sympathetic vasomotor tone. A significant proportion of tonic activity in the RVLM sympathetic premotor neurons is driven by neurons located in a third region of the ventrolateral medulla denominated caudal...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Rostral ventrolateral medulla; Rat; Glutamate; Blood pressure; Caudal pressor area; Sympathetic vasomotor tone.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2008000700002

Prazosin blocks the glutamatergic effects of N-methyl-D-aspartic acid on lordosis behavior and luteinizing hormone secretion in the estrogen-primed female rat
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Landa,A.I.; Cabrera,R.J.; Gargiulo,P.A.
We have observed that intracerebroventricular (icv) injection of selective N-methyl-D-aspartic acid (NMDA)-type glutamatergic receptor antagonists inhibits lordosis in ovariectomized (OVX), estrogen-primed rats receiving progesterone or luteinizing hormone-releasing hormone (LHRH). When NMDA was injected into OVX estrogen-primed rats, it induced a significant increase in lordosis. The interaction between LHRH and glutamate was previously explored by us and another groups. The noradrenergic systems have a functional role in the regulation of LHRH release. The purpose of the present study was to explore the interaction between glutamatergic and noradrenergic transmission. The action of prazosin, an alpha1- and alpha2b-noradrenergic antagonist, was studied...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Sexual behavior; Glutamate; Luteinizing hormone; Noradrenergic transmission; Prazosin; N-methyl-D-aspartic acid.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2006000300007

Increased levels of glutamate in the central nervous system are associated with behavioral symptoms in experimental malaria
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Miranda,A.S.; Vieira,L.B.; Lacerda-Queiroz,N.; Souza,A.H.; Rodrigues,D.H.; Vilela,M.C.; Gomez,M.V.; Machado,F.S.; Rachid,M.A.; Teixeira,A.L.
Cerebral malaria (CM) is a severe complication resulting from Plasmodium falciparum infection. This condition has been associated with cognitive, behavioral and motor dysfunctions, seizures and coma. The underlying mechanisms of CM are incompletely understood. Glutamate and other metabolites such as lactate have been implicated in its pathogenesis. In the present study, we investigated the involvement of glutamate in the behavioral symptoms of CM. Seventeen female C57BL/6 mice (20-25 g) aged 6-8 weeks were infected with P. berghei ANKA by the intraperitoneal route using a standardized inoculation of 10(6) parasitized red blood cells suspended in 0.2 mL PBS. Control animals (N = 17) received the same volume of PBS. Behavioral and neurological symptoms were...
Tipo: Info:eu-repo/semantics/other
Palavras-chave: Cerebral malaria; Glutamate; Cerebrospinal fluid; Behavioral changes; SHIRPA.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2010001200006

Glutamate-N-methyl-D-aspartate receptor modulation and minocycline for the treatment of patients with schizophrenia: an update
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Chaves,C.; Marque,C.R.; Trzesniak,C.; Machado de Sousa,J.P.; Zuardi,A.W.; Crippa,J.A.S.; Dursun,S.M.; Hallak,J.E.
Growing consistent evidence indicates that hypofunction of N-methyl-D-aspartate (NMDA) transmission plays a pivotal role in the neuropathophysiology of schizophrenia. Hence, drugs which modulate NMDA neurotransmission are promising approaches to the treatment of schizophrenia. The aim of this article is to review clinical trials with novel compounds acting on the NMDA receptor (NMDA-R). This review also includes a discussion and translation of neuroscience into schizophrenia therapeutics. Although the precise mechanism of action of minocycline in the brain remains unclear, there is evidence that it blocks the neurotoxicity of NMDA antagonists and may exert a differential effect on NMDA signaling pathways. We, therefore, hypothesize that the effects of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Schizophrenia; NMDA agonist; Glycine; Glutamate; Clinical trial; Minocycline.
Ano: 2009
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2009001100002

Electrophysiological evidence for glial-subtype glutamate transporter functional expression in rat cerebellar granule neurons
Provedor de dados: Brazilian Journal of Medical and Biological Research
Autores: Mafra,R.A.; Leão,R.M.; Beirão,P.S.L.; Cruz,J.S.
A glutamate-sensitive inward current (Iglu) is described in rat cerebellar granule neurons and related to a glutamate transport mechanism. We examined the features of Iglu using the patch-clamp technique. In steady-state conditions the Iglu measured 8.14 ± 1.9 pA. Iglu was identified as a voltage-dependent inward current showing a strong rectification at positive potentials. L-Glutamate activated the inward current in a dose-dependent manner, with a half-maximal effect at about 18 µM and a maximum increase of 51.2 ± 4.4%. The inward current was blocked by the presence of dihydrokainate (0.5 mM), shown by others to readily block the GLT1 isoform. We thus speculate that Iglu could be attributed to the presence of a native glutamate transporter in cerebellar...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Cerebellar granule neurons; Excitatory amino-acid transporter type 2; Patch-clamp; Glutamate; Whole-cell voltage-clamp.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2003000700018

ω-conotoxin MVIIA intralesional injection in spinal cord injury in rats
Provedor de dados: Ciência Rural
Autores: Oliveira,Karen Maciel de; Binda,Nancy Scardua; Lavor,Mário Sérgio Lima; Silva,Carla Maria Osório; Rosado,Isabel Rodrigues; Taguchi,Tatiana Malagoli; Alves,Endrigo Gabellini Leonel; Melo,Marília Martins; Gomez,Marcus Vinícius; Melo,Eliane Gonçalves de.
This study aimed to investigate the neuroprotective effect of ω-conotoxin MVIIA (MVIIA) intralesional application in rats submitted to spinal cord injury. Male Wistar rats, weighing 300g±23.4, were distributed in five groups: negative control (SHAM), placebo (PLA), 5μM MVIIA, 10μM MVIIA and 20μM MVIIA MVIIA. After laminectomy of the 12th thoracic vertebra (SHAM), the PLA, 5μM MVIIA, 10μM MVIIA and 20μM MVIIA groups were subjected to acute compressive spinal cord trauma for five minutes, and then five minutes later, the animals received specific treatment in a standard total volume of 2µL, by intralesional route, using sterile PBS as placebo. Locomotor activity was assayed using Basso Beattie Bresnahan (BBB) scale to show the patterning of SCI. With 48...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: MVIIA; Cone snail; Cell viability; Glutamate; Reactive oxygen species; Lipid peroxidation.
Ano: 2016
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782016000100150