Abstract:
:The glutamine cycle has been proposed as a pathway in which glutamine synthesized in glia provides substrate for synthesis of the neurotransmitters glutamate and GABA as they are lost from neurons. To test whether GABA may regulate this pathway, the effect of elevated GABA on the glial enzyme glutamine synthetase was examined in rat brain. Repeated subcutaneous injections of the antiepileptic GABA transaminase inhibitor gamma-vinylGABA at a dose of 150 mg/kg per day for 21 days reduced glutamine synthetase activity by 36% in the cortex and 22% in the cerebellum. At 30 mg/kg per day, glutamine synthetase activity was reduced by 9.5% in the cortex but unchanged in the cerebellum. The reductions were brain specific because the skeletal muscle and liver enzymes were unaffected by gamma-vinylGABA administration. Amino acid analysis of the cortex from gamma-vinylGABA-treated rats demonstrated a 270% increase in GABA levels after 150 mg/kg but no change after 30 mg/kg. GABA levels and glutamine synthetase activity were inversely correlated. The 150 mg/kg dose significantly lowered cortical glutamine and glutamate levels. The decline in brain glutamine synthetase activity with chronic gamma-vinylGABA administration developed gradually over time and may be due to the slow turnover of this enzyme in vivo.
journal_name
J Neurochemjournal_title
Journal of neurochemistryauthors
Waniewski RA,Martin DLdoi
10.1046/j.1471-4159.1995.65010355.xsubject
Has Abstractpub_date
1995-07-01 00:00:00pages
355-62issue
1eissn
0022-3042issn
1471-4159journal_volume
65pub_type
杂志文章abstract::The glial-derived neurotrophic protein S100beta has been implicated in the development and maintenance of the nervous system. S100beta has also been postulated to play a role in mechanisms of neuropathology because of its specific localization and selective overexpression in Alzheimer's disease. However, the exact rel...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1046/j.1471-4159.1997.69062294.x
更新日期:1997-12-01 00:00:00
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doi:10.1046/j.1471-4159.1998.70031094.x
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journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1986.tb01752.x
更新日期:1986-05-01 00:00:00
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journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1983.tb11322.x
更新日期:1983-02-01 00:00:00
abstract::3,4-Methylenedioxymethamphetamine (MDMA; 'Ecstasy') is a popular recreational drug used worldwide. This study aimed to determine the effects of this compound on the expression of nerve terminal serotonergic markers in rats. Experiment 1 investigated MDMA-induced changes in levels of the serotonin transporter (SERT) an...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.2009.06515.x
更新日期:2010-02-01 00:00:00
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journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1981.tb10840.x
更新日期:1981-06-01 00:00:00
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journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1046/j.1471-4159.1994.63041477.x
更新日期:1994-10-01 00:00:00
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journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.2005.03214.x
更新日期:2005-08-01 00:00:00
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journal_title:Journal of neurochemistry
pub_type: 杂志文章,评审
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更新日期:2012-01-01 00:00:00
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journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1991.tb08187.x
更新日期:1991-02-01 00:00:00
abstract::Experimental allergic encephalomyelitis (EAE) is an autoimmune, animal model of multiple sclerosis (MS) in which demyelination and paralysis are evident. Quinolinic acid (QUIN) is a neurotoxin and endogenous N-methyl-D-aspartate receptor agonist formed from tryptophan. The role of neurotoxins in general and QUIN in pa...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1046/j.1471-4159.1995.64031192.x
更新日期:1995-03-01 00:00:00
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journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.2005.03030.x
更新日期:2005-04-01 00:00:00
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journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1981.tb02406.x
更新日期:1981-01-01 00:00:00
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journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1046/j.1471-4159.2002.00822.x
更新日期:2002-04-01 00:00:00
abstract::Neurofibrillary tangles, one of the major pathological hallmarks of Alzheimer-diseased brains, consist primarily of aggregated paired helical filaments (PHFs) of hyperphosphorylated tau protein. Tau from normal brain and especially from foetal brain is also phosphorylated on some of the sites phosphorylated in PHFs, m...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1046/j.1471-4159.1997.69010191.x
更新日期:1997-07-01 00:00:00
abstract::Glycogen synthase kinase 3 (GSK3) plays important roles in Wnt and insulin signaling, cell fate determination, and Alzheimer-like tau phosphorylation. We discovered an isoform of tau protein kinase I (TPKI)/GSK3beta with a 13 amino acid insert in the catalytic domain owing to alternative splicing. The alternative tran...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1046/j.1471-4159.2002.00918.x
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journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1046/j.1471-4159.2000.0752478.x
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journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1985.tb08761.x
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journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1990.tb04941.x
更新日期:1990-11-01 00:00:00
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journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/jnc.14006
更新日期:2017-05-01 00:00:00
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journal_title:Journal of neurochemistry
pub_type: 杂志文章
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abstract::cDNAs encoding four isoforms of the human NMDA receptor (NMDAR) NMDAR2C (hNR2C-1, -2, -3, and -4) have been isolated and characterized. The overall identity of the deduced amino acid sequences of human and rat NR2C-1 is 89.0%. The sequences of the rat and human carboxyl termini (Gly925-Val1,236) are encoded by differe...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1046/j.1471-4159.1998.71051953.x
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journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1046/j.1471-4159.2003.01632.x
更新日期:2003-03-01 00:00:00
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pub_type: 杂志文章
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journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1987.tb01028.x
更新日期:1987-11-01 00:00:00
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journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1990.tb04957.x
更新日期:1990-11-01 00:00:00
abstract::The major component of the amyloid deposition that characterizes Alzheimer's disease is the 4-kDa beta A4 protein, which is derived from a much larger amyloid protein precursor (APP). A procedure for the complete purification of APP from human brain is described. The same amino terminal sequence of APP was found in tw...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.1992.tb08465.x
更新日期:1992-10-01 00:00:00
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journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1046/j.1471-4159.1997.68020710.x
更新日期:1997-02-01 00:00:00
abstract::Mouse models of MPTP intoxication have been used extensively to explore the molecular mechanisms of Parkinson's disease. However, these models present some limitations since; (i) Dopaminergic (DA) cell death occurs rapidly in contrast to the presumably slow evolution of the disease process. (ii) Some of the key histol...
journal_title:Journal of neurochemistry
pub_type: 杂志文章
doi:10.1111/j.1471-4159.2008.05651.x
更新日期:2008-11-01 00:00:00