Linked Life Data

7815462

Source:http://linkedlifedata.com/resource/pubmed/id/7815462

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
1995-2-3
pubmed:abstractText
Glucose utilization and glycogen turnover was studied by 13C-NMR in segments of hog carotid artery smooth muscle. After superfusion of carotid segments for 8-16 h at 37 degrees C with C-1 labeled glucose. 13C-NMR spectra revealed substantial incorporation into glycogen, lactate and into resonances tentatively identified as glutamate at the C-2 and C-4 positions. The rate of net glycogen incorporation was approximately linear over 8 h in unstimulated muscle. After washing out the initial labeled glucose, carotids were contracted by 80 mM KCl in the presence of C-2 labeled glucose. During the contraction simultaneous flux of glycogenolysis and glycolysis was observed with production of lactate labeled at the C-2 position (from glucose labeled at the second carbon) and with the magnitude of the glycogen resonance decreasing. However, no lactate labeled at the C-3 position (derived from C-3 glycogen) was observed at the end of a prolonged contraction. If complete mixing of the intermediates of the two pathways occurred, lactate derived from both glucose and glycogen would have been observed. When similar experiments are performed in the presence of 5 mM NaCN to block oxidative metabolism, then lactate derived from glucose and from glycogen was clearly observed. Therefore, when oxidative metabolism was intact, the intermediates of glycogenolysis and glycolysis did not normally appear to fully mix despite simultaneous flux of the two pathways during contraction. These separable cytosolic pathways for carbohydrate utilization are proposed to be governed by a reaction-diffusion class of mechanism. Such an organization of cytosolic enzymes may represent a general feature of cell metabolism.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0022-2828
pubmed:author
pubmed:issnType
Print
pubmed:volume
26
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1197-210
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Simultaneous and separable flux of pathways for glucose and glycogen utilization studied by 13C-NMR.
pubmed:affiliation
Department of Radiology, University of Washington, Seattle 98195.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't