Linked Life Data

8691096

Source:http://linkedlifedata.com/resource/pubmed/id/8691096

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1996-8-29
pubmed:abstractText
While numerous researchers have used rat models to investigate the in vivo actions of IGF-I, interpretation of the results in terms of true concentrations of rat IGF-I (rIGF-I) in plasma has been hampered by the absence of homologous reference standards. In order to overcome this we have produced recombinant rIGF-I (rrIGF-I) from Escherichia coli using procedures similar to those we have previously described for the production of other recombinant IGFs. The rrIGF-I is indistinguishable from serum-derived rIGF-I when characterized in a number of in vitro assays including ability to stimulate protein synthesis and inhibit protein degradation in cultured rat cells, as well as in interactions with the rat type-1 IGF receptor and with rat IGF-binding proteins. Moreover, both the serum-derived and the recombinant rat proteins are similar to recombinant human IGF-I (rhIGF-I) in these assays. However, differences between the human and rat IGFs are apparent when tested in immunoassays using some antibodies raised against rhIGF-I. Furthermore, the differences between rhIGF-I and rrIGF-I are even greater when rhIGF-I is used as the competing radiolabel in these assays, a situation that can lead to a two- to threefold underestimation of the actual concentration of IGF-I in rat plasma. These results indicate that, while immunoassays employing antibodies raised against rhIGF-I and rhIGF-I reference standards reliably indicate trends in IGF-I concentrations in rat plasma, the true amounts of rIGF-I present can only be assured in an assay using homologous tracer and reference peptides.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0022-0795
pubmed:author
pubmed:issnType
Print
pubmed:volume
149
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
379-87
pubmed:dateRevised
2004-11-17
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Characterization of serum-derived and recombinant rat IGF-I and their use for measuring true concentrations of IGF-I in rat plasma.
pubmed:affiliation
Cooperative Research Centre for Tissue Growth and Repair, CSIRO Division of Human Nutrition, Adelaide, South Australia.
pubmed:publicationType
Journal Article