Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
2000-9-29
pubmed:abstractText
An understanding of the metabolic fate of radiometal-labeled peptides is important due to their application in the areas of diagnostic imaging and targeted radiotherapy. Radioisotopes of copper ((64)Cu, T(1/2) = 12.7 h; (67)Cu, T(1/2) = 62 h) have been labeled to monoclonal antibodies (mAbs) and peptides and have applications in the areas of PET imaging and targeted radiotherapy of cancer. Copper-64-TETA-D-Phe(1)-octreotide ([(64)Cu]TETA-OC) has been shown to bind to the somatostatin receptor, both in vitro and in vivo, and this agent inhibited the growth of somatostatin-receptor positive tumors in rats. Copper-64-TETA-OC, however, showed a retention of activity in the blood, liver, and bone marrow, suggesting possible dissociation of (64)Cu from TETA-OC in vivo. The purpose of this study was to determine if (64)Cu dissociates from [(64)Cu]TETA-OC and binds to the protein, superoxide dismutase (SOD) in rat liver. The liver metabolism of [(64)Cu]TETA-OC was examined in normal rats using a gel-electrophoresis assay specific for SOD and size-exclusion chromatography. The major metabolite in rat liver at 20 h postinjection had a molecular weight of 32 kDa as shown by size-exclusion chromatography. A gel electrophoresis assay specific for the detection of SOD [nitro-blue tetrazolium (NBT)] showed that a (64)Cu-labeled protein isolated from rat liver homogenates comigrated with SOD. Evaluating the metabolic fate of copper radiopharmaceuticals demonstrated that Cu(II) dissociates from macrocyclic chelators such as TETA and binds to proteins in high concentrations, namely SOD in rat liver.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
1043-1802
pubmed:author
pubmed:issnType
Print
pubmed:volume
11
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
527-32
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:articleTitle
In vivo transchelation of copper-64 from TETA-octreotide to superoxide dismutase in rat liver.
pubmed:affiliation
Mallinckrodt Institute of Radiology, Washington University School of Medicine, 510 South Kingshighway Boulevard, Campus Box 8225, Saint Louis, Missouri 63110, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.