In vivo metabolism of I-123 labeled semisynthetic low density lipoproteins

Technical Report · Sat Dec 01 00:00:00 EST 1990

DOI:https://doi.org/10.2172/7185351· OSTI ID:7185351

Harper, P V

We previously observed that small model beta-strand peptides (MBPs) selectively bind to human low density lipoprotein (hLDL) in vitro, and that some MBPs can be labeled with I-123-tyramine cellobiose (I-123-TyC). We hypothesized that metabolism of semisynthetic hLDL should mimic that of covalently labeled native hLDL, and planned to evaluate the biodistribution in rabbits of semisynthetic hLDL; to determine effects of prior oxidation and acetylation of the adsorbing hLDL on binding of MBPs and upon biodistribution of semisynthetic particles; and to begin biodistribution studies with semisynthetic hLDL in human subjects, with the eventual goal of application to experimental and clinical nuclear imaging studies. We have synthesized a radioiodotyrosine-containing MBP, designated betay, as a more suitable adsorbant to hLDL thanradioiodine-TyC-MBP, and optimized conditions for preparing radioiodine-betaY:hLDL. In rabbits both betaY and betaY:hLDL complexes were cleared from the bloodstream much more rapidly than radioiodine-TyC-hLDL or In-111-hLDL, and betaY in either form showed a biodistribution pattern different from that of directly radiolabeled hLDL. Even though radioiodine-betaY can be quickly and easily produced, we conclude that neither betaY alone nor semisynthetic betaY:hLDL particles are likely to prove useful as tracers of hLDL metabolism in vivo.

• Research Organization: Chicago Univ., IL (United States)
• Sponsoring Organization: USDOE; USDOE, Washington, DC (United States)
• DOE Contract Number: FG02-88ER60725
• OSTI ID: 7185351
• Report Number(s): DOE/ER/60725-1; ON: DE92040343
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
59 BASIC BIOLOGICAL SCIENCES
LIPOPROTEINS
CATABOLISM
TISSUE DISTRIBUTION
BIOLOGICAL HALF-LIFE
CHEMICAL PREPARATION
IN VIVO
IODINE 123
LABELLING
MAN
PROGRESS REPORT
RABBITS
RADIOPHARMACEUTICALS
TRACER TECHNIQUES
TYROSINE
AMINO ACIDS
ANIMALS
BETA DECAY RADIOISOTOPES
CARBOXYLIC ACIDS
DISTRIBUTION
DOCUMENT TYPES
DRUGS
ELECTRON CAPTURE RADIOISOTOPES
HOURS LIVING RADIOISOTOPES
HYDROXY ACIDS
INTERMEDIATE MASS NUCLEI
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
LABELLED COMPOUNDS
LIPIDS
MAMMALS
METABOLISM
NUCLEI
ODD-EVEN NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
PRIMATES
PROTEINS
RADIOISOTOPES
SYNTHESIS
VERTEBRATES
550601* - Medicine- Unsealed Radionuclides in Diagnostics
550501 - Metabolism- Tracer Techniques