Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1988-10-19
pubmed:abstractText
Both ammonia and beta-methylene-DL-aspartate (beta-MA), an irreversible inhibitor of aspartate aminotransferase activity and thus of the malate-aspartate shuttle, were found previously to decrease oxidative metabolism in cerebral cortex slices. In the present work, the possibility that ammonia and beta-MA affect energy metabolism by a common mechanism (i.e., via inhibition of the malate-aspartate shuttle) was investigated using primary cultures of neurons and astrocytes. Incubation of astrocytes for 30 min with 5 mM beta-MA resulted in a decreased production of 14CO2 from [U-14C]glucose, but did not affect 14CO2 production from [2-14C]pyruvate. Conversely, incubation of astrocytes with 3 mM ammonium chloride resulted in decreased 14CO2 production from [2-14C]pyruvate, but 14CO2 production from [U-14C]glucose was not significantly affected. Ammonium chloride had no significant effect on 14CO2 production from either [U-14C]glucose or [2-14]pyruvate by neurons. However, incubation of neurons with beta-MA or beta-MA plus ammonium chloride resulted in a approximately 45% decrease of 14CO2 production from both [U-14C]glucose and [2-14C]pyruvate. A 2-h incubation of astrocytes with beta-MA resulted in no change in ATP levels, but a 35% decrease in phosphocreatine. Similar treatment of neurons resulted in greater than 50% decrease in ATP, but had little effect on phosphocreatine. beta-MA also caused a decrease in glutamate and aspartate content of neurons, but not of astrocytes. The different metabolic responses of neurons and astrocytes towards beta-MA were probably not due to a differential inhibition of aspartate aminotransferase which was inhibited by approximately 45% in astrocytes and by approximately 55% in neurons.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0022-3042
pubmed:author
pubmed:issnType
Print
pubmed:volume
51
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1197-203
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Effects of ammonia and beta-methylene-DL-aspartate on the oxidation of glucose and pyruvate by neurons and astrocytes in primary culture.
pubmed:affiliation
Department of Neurology, Cornell University Medical College, New York, NY 10021.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't