Linked Life Data

10462368

Source:http://linkedlifedata.com/resource/pubmed/id/10462368

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1999-9-16
pubmed:abstractText
Brain edema sufficient to cause intracranial hypertension and brain herniation remains a major cause of mortality in acute liver failure (ALF). Studies in experimental animal models of ALF suggest a role for ammonia in the pathogenesis of both encephalopathy and brain edema in this condition. As part of a series of studies to evaluate the therapeutic efficacy of ammonia-lowering agents, groups of rats with ALF caused by hepatic devascularization were treated with L-ornithine-L-aspartate (OA), an agent shown previously to be effective in reducing blood ammonia concentrations in both experimental and human chronic liver failure. Treatment of rats in ALF with infusions of OA (0.33 g/kg/h, intravenously) resulted in normalization of plasma ammonia concentrations and in a significant delay in onset of severe encephalopathy. More importantly, brain water content was significantly reduced in OA-treated rats with ALF. These protective effects of OA were accompanied by increased plasma concentrations of several amino acids including glutamate, gamma-aminobutyric acid (GABA), taurine, and alanine, as well as the branched-chain amino acids, leucine, isoleucine, and valine. Increased availability of glutamate following OA treatment provides the substrate for the major ammonia-removal mechanism (glutamine synthetase). Plasma (but not cerebrospinal fluid) glutamine concentrations were increased 2-fold (P <.02) in OA-treated rats, consistent with increased muscle glutamine synthesis. Direct measurement of glutamine synthetase activities revealed a 2-fold increase following OA treatment. These findings demonstrate a significant ammonia-lowering effect of OA together with a protective effect on the development of encephalopathy and brain edema in this model of ALF.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0270-9139
pubmed:author
pubmed:issnType
Print
pubmed:volume
30
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
636-40
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1999
pubmed:articleTitle
L-ornithine-L-aspartate lowers plasma and cerebrospinal fluid ammonia and prevents brain edema in rats with acute liver failure.
pubmed:affiliation
Neuroscience Research Unit, Centre Hospitalier de l'Université de Montréal (Campus Saint-Luc), Montreal, Que., Canada H2X 3J4.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't