Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1990-10-2
pubmed:abstractText
The effects of hyperammonemia on brain function have been studied in three different experimental models in the rat: acute liver ischemia, urease-treated animals and methionine sulfoximine-treated animals. To quantify the development of encephalopathy, clinical grading and electroencephalographic spectral analysis were used as indicators. In all three experimental models brain ammonia concentrations increased remarkably associated with comparable increases in severity of encephalopathy. Furthermore, in vivo 1H-nuclear magnetic resonance spectroscopy of a localized cerebral cortex region showed a decrease in glutamate concentration in each of the aforementioned experimental models. This decreased cerebral cortex glutamate concentration was confirmed by biochemical analysis of cerebral cortex tissue post mortem. Furthermore, an increase in cerebral cortex glutamine and lactate concentration was observed in urease-treated rats and acute liver ischemia rats. As expected, no increase in cerebral cortex glutamine was observed in methionine sulfoximine-treated rats. These data support the hypothesis that ammonia is of key importance in the pathogenesis of acute hepatic encephalopathy. Decreased availability of cerebral cortex glutamate for neurotransmission might be a contributing factor to the pathogenesis of hyperammonemic encephalopathy. A surprising new finding revealed by 1H-nuclear magnetic resonance spectroscopy was a decrease of cerebral cortex phosphocholine compounds in all three experimental models. The significance of this finding, however, remains speculative.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0270-9139
pubmed:author
pubmed:issnType
Print
pubmed:volume
12
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
281-90
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:1975248-Acute Disease, pubmed-meshheading:1975248-Ammonia, pubmed-meshheading:1975248-Animals, pubmed-meshheading:1975248-Brain, pubmed-meshheading:1975248-Brain Diseases, pubmed-meshheading:1975248-Electroencephalography, pubmed-meshheading:1975248-Glutamates, pubmed-meshheading:1975248-Glutamic Acid, pubmed-meshheading:1975248-Ischemia, pubmed-meshheading:1975248-Lactates, pubmed-meshheading:1975248-Lactic Acid, pubmed-meshheading:1975248-Liver Circulation, pubmed-meshheading:1975248-Liver Diseases, pubmed-meshheading:1975248-Magnetic Resonance Spectroscopy, pubmed-meshheading:1975248-Male, pubmed-meshheading:1975248-Methionine Sulfoximine, pubmed-meshheading:1975248-Protons, pubmed-meshheading:1975248-Rats, pubmed-meshheading:1975248-Rats, Inbred Strains, pubmed-meshheading:1975248-Urease
pubmed:year
1990
pubmed:articleTitle
Changes in brain metabolism during hyperammonemia and acute liver failure: results of a comparative 1H-NMR spectroscopy and biochemical investigation.
pubmed:affiliation
Laboratory of Experimental Medicine, University of Amsterdam, The Netherlands.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't