Indium-111-Labeled LDL: A Potential Agent for Imaging Atherosclerotic Disease and Lipoprotein Biodistribution

• Published in: The Journal of nuclear medicine (1978) Vol. 31; no. 3; pp. 343 - 350
• Main Authors: Rosen, Joel M, Butler, S. Patrick, Meinken, George E, Wang, Theodore S. T, Ramakrishnan, Rajasekhar, Srivastava, Suresh C, Alderson, Philip O, Ginsberg, Henry N
• Format: Journal Article
• Language: English
• Published: United States Soc Nuclear Med 01.03.1990
• Subjects: 550601 - Medicine- Unsealed Radionuclides in Diagnostics; ADRENAL GLANDS; AMINO ACIDS; ANIMALS; ARTERIOSCLEROSIS; BETA DECAY RADIOISOTOPES; BIOCHEMICAL REACTION KINETICS; BODY; CARBOXYLIC ACIDS; CARDIOVASCULAR DISEASES; CENTRIFUGATION; CHELATING AGENTS; Coronary Artery Disease - diagnostic imaging; DAYS LIVING RADIOISOTOPES; DIAGNOSIS; DISEASES; DISTRIBUTION; DRUGS; DTPA; ELECTRON CAPTURE RADIOISOTOPES; ELECTROPHORESIS; ENDOCRINE GLANDS; GLANDS; Humans; Hypercholesterolemia - diagnostic imaging; IMAGE PROCESSING; INDIUM 111; INDIUM ISOTOPES; Indium Radioisotopes; INTERMEDIATE MASS NUCLEI; ISOMERIC TRANSITION ISOTOPES; ISOTOPES; KINETICS; LIPIDS; LIPOPROTEINS; Lipoproteins, LDL - pharmacokinetics; Male; MAMMALS; MEMBRANE PROTEINS; MINUTES LIVING RADIOISOTOPES; NUCLEI; ODD-EVEN NUCLEI; ORGANIC ACIDS; ORGANIC COMPOUNDS; ORGANS; Pentetic Acid; PROCESSING; PROTEINS; RABBITS; RADIOISOTOPES; RADIOLOGY AND NUCLEAR MEDICINE; Radionuclide Imaging; RADIOPROTECTIVE SUBSTANCES; REACTION KINETICS; RECEPTORS; Receptors, LDL - metabolism; SEPARATION PROCESSES; TISSUE DISTRIBUTION; ULTRACENTRIFUGATION; VASCULAR DISEASES; VERTEBRATES
• ISSN: 0161-5505; 1535-5667

Radiolabeling of low-density lipoprotein (LDL) and external imaging with a gamma camera would offer a means of taking advantage of the metabolic activity of developing atherosclerotic lesions in order to noninvasively detect and determine the extent of atherosclerotic cardiovascular disease. Indium-111-(111In) labeled LDL was prepared and its purity demonstrated by agarose electrophoresis and ultracentrifugation. In vitro studies with cultured human fibroblasts demonstrated significant inhibition of iodine-125-(125I) LDL binding to LDL receptors by 111In-LDL, although this was less than the inhibition produced by unlabeled LDL. Adrenal gland uptake of 111In-LDL by hypercholesterolemic rabbits was reduced by 86% compared to the level of uptake observed in normal rabbits. These results were compatible with downregulation of adrenal LDL receptors in the hypercholesterolemic rabbits. Uptake of 111In-LDL in the atherosclerotic proximal aorta of hypercholesterolemic rabbits was 2.5 times higher than in normal rabbits. These results suggest that 111In-LDL has the potential to be a useful agent for external imaging of atherosclerotic lesions and lipoprotein biodistribution.