Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1985-9-3
pubmed:abstractText
Residualizing radioactive labels are designed to remain entrapped within cells following degradation of a carrier protein, and have been used for identification of the tissue and cellular sites of plasma protein catabolism. In this study we describe a convenient synthesis and purification of a series of 125I-labeled glycoconjugates, and an evaluation of their efficiency of retention in liver following degradation of a model carrier protein, asialofetuin. Glycoconjugates were prepared in 65-90% yield by reductive amination of reducing sugars with aromatic amines using NaBH3CN. The products were purified in a single ion-exchange chromatographic step, and then labeled with 125I. The derivatives prepared were mono-and disubstituted lactitol-,cellobiitol-and glucitol-[125I]tyramine and lactitol-[125I]tyrosine. 125I-Glycoconjugates were coupled to asialofetuin using either cyanuric chloride or, for lactose-containing labels, by treatment with galactose oxidase followed by reductive amination with NaBH3CN. Attachment of labels by either procedure did not affect the normal rapid clearance of asialofetuin from the rat circulation nor its uptake and degradation in liver lysosomes. Leakage of 125I-labeled degradation products from cells was measured by following the kinetics of loss of whole-body radioactivity. We observed that degradation products from larger, disubstituted glycoconjugates were retained more efficiently than those from smaller and monosubstituted derivatives, and that glycoconjugates coupled to protein via reductive amination were retained in the body more efficiently than those coupled by cyanuric chloride. Overall, dilactitol-[125I]tyramine coupled to protein by reductive amination was entrapped most efficiently in liver.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0003-9861
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
240
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
635-45
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed-meshheading:2411222-Animals, pubmed-meshheading:2411222-Asialoglycoproteins, pubmed-meshheading:2411222-Chemical Phenomena, pubmed-meshheading:2411222-Chemistry, pubmed-meshheading:2411222-Female, pubmed-meshheading:2411222-Fetuins, pubmed-meshheading:2411222-Iodine Radioisotopes, pubmed-meshheading:2411222-Isotope Labeling, pubmed-meshheading:2411222-Liver, pubmed-meshheading:2411222-Male, pubmed-meshheading:2411222-Metabolic Clearance Rate, pubmed-meshheading:2411222-Muscles, pubmed-meshheading:2411222-Myocardium, pubmed-meshheading:2411222-Protein Conformation, pubmed-meshheading:2411222-Proteins, pubmed-meshheading:2411222-Rats, pubmed-meshheading:2411222-Sorbitol, pubmed-meshheading:2411222-Sugar Alcohols, pubmed-meshheading:2411222-Tyramine, pubmed-meshheading:2411222-Tyrosine, pubmed-meshheading:2411222-alpha-Fetoproteins
pubmed:year
1985
pubmed:articleTitle
125I-glycoconjugate labels for identifying sites of protein catabolism in vivo: effect of structure and chemistry of coupling to protein on label entrapment in cells after protein degradation.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.