Linked Life Data

1276223

Source:http://linkedlifedata.com/resource/pubmed/id/1276223

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1976-9-1
pubmed:abstractText
As part of a systematic study of alcoholism and thiamine absorption, the effect of diet-induced thiamine deficiency and the role of the unstirred water layer on the thiamine transport were investigated. Using 3H-labeled dextran as a marker of adherent mucosal volume, jejunal uptake of 14C-labeled thiamine hydrochloride was measured, in vitro, in thiamine-deficient rats and pair-fed controls. Uptake of low thiamine concentrations (0.2 and 0.5 muM) was greater in the thiamine-deficient rats than in the controls. In contrast, uptake rates for high thiamine concentrations (20 and 50 muM) were similar in both groups. While Jmax was unaltered, Km was decreased in thiamine deficiency, suggesting a decrease in unstirred water layer thickness. Accordingly, the thickness of the water layer was measured in both groups of animals and correlated with Jmax and Km under unstirred and stirred conditions. Without stirring, there was no difference in Jmax between the two groups. In contrast, both Km and the water layer were reduced in the thiamine-deficient rats. With stirring, Jmax was not affected, but both Km and the water layer thickness were reduced to similar values in both groups. Reversal of thiamine deficiency resulted in the return of thiamine uptake and the unstirred water layer thickness to control values. These data support the concept of a dual system of thiamine transport and emphasize the role of the unstirred water layer as an important determinant of transport kinetics not only under physiologic situations but also in diet-induced rat thiamine deficiency, a model for a clinical patholigical state. The decrease in the unstirred water layer thickness in thiamine deficiency may be also viewed as a possible adaptive mechanism to facilitate absorption of meager supplies of thiamine.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
17
pubmed:volume
436
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
438-47
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1976
pubmed:articleTitle
Thiamine transport in thiamine-deficient rats. Role of the unstirred water layer.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.