Linked Life Data

6129977

Source:http://linkedlifedata.com/resource/pubmed/id/6129977

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1983-3-17
pubmed:abstractText
A two-stage surgical occlusion of the portal vein was employed to produce hyperammonaemia in the rat. The procedure resulted in a significant rise of arterial blood ammonia level from 70 . 5 +/- 6 . 5 mumol/l (mean +/- SEM, n = 10) to 214 . 0 +/- 37 . 7 mumol/l and in a rise of venous blood ammonia from 65 . 0 +/- 9 . 4 mumol/l to 122 . 2 +/- 7 . 4 mumol/l during the first day following the complete vein occlusion. A marked increase of the arteriovenous difference of ammonia concentration from virtually zero in sham-operated controls to 72 +/- 9 (n = 8) mumol/l in rats 1 day after the surgical manipulation suggested uptake of ammonia by skeletal muscle. Rat muscle glutamine synthetase activity increased from 0 . 46 +/- 0 . 06 u/mg (n = 7) in controls to 2 . 7 +/- 0 . 3 u/mg (n = 7) on the fourth day following portal vein ligation, and muscle branched chain amino acids aminotransferase increased from 0 . 2 +/- 0 . 05 u/mg in controls to 0 . 96 +/- 0 . 1 u/mg (n = 7) during the first day of ligation. Glutamine dehydrogenase and aspartate aminotransferase activities were not affected by the surgical procedure. These observations suggest that ammonia trapping in skeletal muscle is coupled to glutamine formation via amination of glutamic acid. This conclusion was further supported by the finding that ammonia uptake correlated (r = 0 . 92) with enhanced release of glutamine from muscle and that treatment with methionine sulfoximine, a potent inhibitor of glutamine synthetase, changed the arteriovenous difference of glutamine from -0 . 92 +/- 0 . 01 mmol/l in ligated animals (net release) to +0 . 12 +/- 0 . 01 mmol/l (net uptake) in ligated and inhibitor-treated animals. Similarly, the inhibitor also abolished the arterio-venous difference of ammonia. Thus, the animal model of hyperammonaemia and the muscle enzyme assays reveal that skeletal muscle is involved in the regulation of blood ammonia level by conversion of ammonia, via glutamic acid, to glutamine.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0014-2972
pubmed:author
pubmed:issnType
Print
pubmed:volume
12
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
445-50
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1982
pubmed:articleTitle
Ammonia uptake by skeletal muscle in the hyperammonaemic rat.
pubmed:publicationType
Journal Article