Advanced Search

Browse by Discipline

Scientific Societies

E-print Alerts

Add E-prints

E-print Network

  Advanced Search  

In Vivo Transchelation of Copper-64 from TETA-Octreotide to Superoxide Dismutase in Rat Liver

Summary: In Vivo Transchelation of Copper-64 from TETA-Octreotide to
Superoxide Dismutase in Rat Liver
Laura A. Bass, Mu Wang, Michael J. Welch, and Carolyn J. Anderson*
Mallinckrodt Institute of Radiology, Washington University School of Medicine, 510 South Kingshighway
Boulevard, Campus Box 8225, Saint Louis, Missouri 63110. Received November 30, 1999;
Revised Manuscript Received May 12, 2000
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
(64Cu, T1/2 ) 12.7 h; 67Cu, T1/2 ) 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-Phe1-octreotide ([64Cu]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 64Cu 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 [64Cu]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


Source: Anderson, Carolyn J. - Department of Molecular Biology and Pharmacology, Washington University in St. Louis


Collections: Biology and Medicine