Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1987-6-1
pubmed:abstractText
We used autoradiography to test the hypothesis that a major function of thyroid hormone-binding proteins in plasma is to ensure uniform distribution of thyroid hormones among cells of a given tissue. The distribution of [125I]T4 within rat hepatic lobules was determined after its single pass perfusion through the portal vein in solutions containing or lacking thyroid hormone-binding proteins. These proteins included thyroid hormone-binding globulin, thyroid hormone-binding prealbumin, and albumin. In the absence of these proteins, virtually all of the perfused T4 was taken up by the periportal cells, and subsequent perfusion with protein-free solution did not cause redistribution of this T4. In the presence of these proteins, in contrast, the perfused T4 was taken up uniformly by all cells within the lobule. Albumin alone was sufficient to ensure uniform cellular uptake of T4. However, variation of oleic acid concentrations within the physiological range markedly influenced the concentration of free T4 in a solution of 4% human serum albumin, but not in human serum. These results indicate that uniform distribution of T4 within tissues requires circulating thyroid hormone-binding proteins, and that the specific binding proteins, thyroid hormone-binding globulin and thyroid hormone-binding prealbumin, are required to ensure nonfluctuating circulating concentrations of free T4 in vivo. Other hormone-binding proteins in plasma and some transport proteins may function similarly.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0013-7227
pubmed:author
pubmed:issnType
Print
pubmed:volume
120
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1742-9
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Thyroid hormone-binding proteins in plasma facilitate uniform distribution of thyroxine within tissues: a perfused rat liver study.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.