Linked Life Data

8404952

Source:http://linkedlifedata.com/resource/pubmed/id/8404952

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
8
pubmed:dateCreated
1993-11-15
pubmed:abstractText
The goal of the present study was to optimize technetium-99m labelling of low-density lipoprotein (LDL) and to investigate the in vitro and in vivo properties of the tracer to determine whether its application for quantitative scintigraphy of hepatic LDL receptor activity is feasible. LDL labelled with iodine-125 by the iodine monochloride method was used as a reference tracer. Comparison of different assessments of radiochemical purity [trichloro-acetic acid precipitation (%ppTCA), paper chromatography, size-exclusion chromatography and chloroform-methanol extraction] exhibited %ppTCA to be superior as a parameter of tracer quality. In spite of a high radiochemical purity immediately after labelling, modifications of 99mTc labelling of LDL did not overcome the poor long-term stability of the tracer. Subsequent dialysis in phosphate buffer over about 3 h sufficiently increased the long-term stability in vitro and in vivo. The competitive recognition of dialysed 99mTc-LDL and 125I-LDL with native LDL by high-affinity binding sites was demonstrated in human hepatoma cells (HepG2) and human fibroblasts. Biodistribution data of simultaneously injected 99mTc-LDL and 125I-LDL in New Zealand White rabbits showed a high uptake of both tracers in tissues with high LDL receptor activity, yet 99mTc-LDL uptake exceeded 125I-LDL uptake by two- to sevenfold. In contrast to 125I-LDL, 99mTc-LDL showed a higher unspecific uptake into the bone marrow and the spleen, suggesting an additional uptake mechanism probably via the scavenger pathway.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0340-6997
pubmed:author
pubmed:issnType
Print
pubmed:volume
20
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
667-73
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Technetium-99m labelled LDL as a tracer for quantitative LDL scintigraphy. I. Tracer purification, in vitro and in vivo long-term stability, in vitro validation and biodistribution.
pubmed:affiliation
University Clinic of Nuclear Medicine, University of Vienna, Austria.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't