Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2006-8-10
pubmed:abstractText
The expression and activities of glucokinase (GK) and hexokinase (HK) were assessed in different tissues of rainbow trout (Oncorhynchus mykiss) under different feeding conditions (fed, fasted for 14 days, and refed for 7 days). Two different HK-I cDNAs were identified with different tissue distributions. One transcript named heart or H-HK-I was observed in the four brain regions assessed, white muscle, kidney, and gills but not in liver or erythrocytes. A second transcript named liver or L-HK-I was found in all tissues surveyed. GK mRNA was identified only in liver and the four brain regions. GK expression was altered by feeding conditions, especially in liver and hypothalamus where food deprivation decreased and re-feeding increased expression; changes in expression reflected activity changes and changes in tissue glycogen levels. In contrast, feeding conditions did not alter expression of either HK-I transcript but did alter tissue HK activities. The reduced phosphorylating capacity noted with food deprivation correlates primarily with changes in tissue HK, whereas increased capacity, as with refeeding, was associated with changes in GK; these changes fit with the different K(m) values of the GK and HK enzymes. These results provide evidence for the hypothalamus acting as a glucosensor in trout, as hyperglycemia produced increased GK expression and activity, as well as increased glycogen levels. Thus, even though trout use glucose poorly, none of the parameters tested here relate to this inability to use glucose and suggest that, at least, rainbow trout, if given an appropriate carbohydrate diet, could metabolically adjust to such a diet.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0363-6119
pubmed:author
pubmed:issnType
Print
pubmed:volume
291
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
R810-21
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Glucokinase and hexokinase expression and activities in rainbow trout tissues: changes with food deprivation and refeeding.
pubmed:affiliation
Laboratorio de Fisioloxía Animal, Departamento de Bioloxía Functional e Ciencias da Saúde, Facultade de Bioloxía, Universidade de Vigo, E-36310 Vigo, Spain. jsoengas@uvigo.es
pubmed:publicationType
Journal Article