Linked Life Data

2370303

Source:http://linkedlifedata.com/resource/pubmed/id/2370303

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1990-8-23
pubmed:abstractText
The effects of pH and anionic binding inhibitors were used to test the hypothesis that the increased T4 binding affinity of the variant albumin (Alb-FDH) of familial dysalbuminemic hyperthyroxinemia (FDH) is due to an electrostatic bond with the ionized phenolic hydroxyl of the iodothyronine. As determined by charcoal adsorption from 2% serum in which binding to T4-binding globulin and transthyretin had been inhibited, increased T4 binding by Alb-FDH was pH dependent and proportional to the ionization of the phenolic hydroxyl. Increased T3 binding became apparent above physiological pH, as is consistent with the higher pK of the T3 phenolic hydroxyl. The iodothyroacetic analogs of T4 and T3 developed maximal increases in binding to Alb-FDH at about the same pH as the corresponding iodothyronines. Aspirin, salicylate, warfarin, and chloride, anions that have minimal stereochemical resemblance to the iodothyronines but bind to albumin cationic groups, inhibited T4 binding to FDH sera at concentrations that had little or no effect on binding in normal sera. Increased displacement of T4 from Alb-FDH by salicylate was also evident at therapeutic ratios to a 1:1 dilution of serum in a dialysis system. Aspirin displaced T4 at a lower pH than T3, as is consistent with competition with the ionized iodothyronine phenolic group. These findings suggest that an electrostatic bond between the iodothyronine phenolate and a cationic group on the protein is the basis for the increased affinity and specificity of Alb-FDH for T4.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0021-972X
pubmed:author
pubmed:issnType
Print
pubmed:volume
71
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
98-104
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Studies on the nature of iodothyronine binding in familial dysalbuminemic hyperthyroxinemia.
pubmed:affiliation
Department of Medicine, State University of New York Health Science Center, Brooklyn 11203-2098.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't