Linked Life Data

3094381

Source:http://linkedlifedata.com/resource/pubmed/id/3094381

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4 Pt 1
pubmed:dateCreated
1986-11-10
pubmed:abstractText
This paper characterizes amino acid (AA) uptake pathways in an everted-sleeve preparation of mouse jejunum. AA uptake is linear with time for 2-4 min, depending on the particular AA and its uptake rate. Escape of tracer to the serosal surface is still negligible at these times. Errors due to metabolism of labeled AAs to volatile products can be minimized by using 14C- rather than 3H-labeled AAs and by not drying tissues before counting. The dependence of AA uptake on concentration shows saturable kinetics, with apparent Km values in the range 1-4 mM. By 25 or 50 mM an uptake plateau is reached for leucine, lysine, methionine, and methylaminoisobutyric acid but not for aspartic acid, histidine, or proline. Proline kinetics are the result of a saturable Na+-dependent component, a linear diffusional component, and possibly a small saturable Na+-independent component. The Na+-dependent component of uptake for six AAs averages 83% of the total at 0.01 mM and 54% at 25 or 50 mM. Leucine and D-glucose exhibit modest (32%) cross-inhibition of Na+-dependent uptake. For the same six AAs we determined the percent inhibition of both the Na+-dependent and the Na+-independent components by the other AAs. These results suggest the presence of at least five or six AA uptake pathways in mouse jejunum: distinct Na+-dependent pathways for acidic, basic, and neutral AAs and for imino acids; a shared Na+-independent pathway for basic and neutral AAs; and possibly a Na+-independent pathway for acidic AAs. Comparisons of AA uptake pathways in mouse, rabbit, and rat intestine reveal many similarities but also some differences.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
251
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
G501-8
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1986
pubmed:articleTitle
Uptake pathways for amino acids in mouse intestine.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S.