Linked Life Data

9420008

Source:http://linkedlifedata.com/resource/pubmed/id/9420008

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
1998-2-2
pubmed:abstractText
To verify research from this laboratory indicating that sheep omasal epithelium contains mRNA encoding for a peptide transporter(s) and to determine di- to octapeptide transport capability, we injected poly(A)+ RNA isolated from sheep omasal epithelium into Xenopus laevis oocytes. Poly(A)+ RNA was functionally expressed in Xenopus oocytes 4 to 7 d after injection. Peptide (5 di-, 10 tri-, 6 tetra-, 2 penta-, 1 hexa-, 1 hepta-, and 1 octapeptide) transport capability was measured by impaling oocytes with a microelectrode to monitor membrane potential (Vm). Oocytes were maintained in pH 5.5 buffer. Peptide transport was identified as being expressed when, in the presence of a buffered peptide substrate (1 mM), the oocyte membrane showed persistent depolarization (a more positive Vm). In the absence of peptide transport, the membrane became depolarized with the addition of buffered substrate, but it rapidly repolarized to the resting potential. Peptide transport was expressed for some di-, tri-, and tetrapeptides. Measured depolarization ranged from 9.6 mV to 42.1 mV. Larger peptides were not transported by the oocytes. When transport expression was measured with the substrates in a pH 7.5 buffer, no transport occurred, indicating that transport was dependent on a proton gradient. Thus, sheep omasal epithelium contains mRNA that codes for a protein(s) capable of proton-dependent di-, tri-, and tetrapeptide transport. Results from the present study provide further evidence that absorption of peptides from the ruminant stomach is possible.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0021-8812
pubmed:author
pubmed:issnType
Print
pubmed:volume
75
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3323-30
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Poly(A)+ RNA from sheep omasal epithelium induces expression of a peptide transport protein(s) in Xenopus laevis oocytes.
pubmed:affiliation
Department of Animal and Poultry Sciences, Virginia Polytechnic Institute and State University, Blacksburg 24061-0306, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't