Evaluation of 99mTc-LDL for studying lipoprotein metabolism and imaging atherosclerotic lesions in vivo

Conference · Wed May 01 04:00:00 EDT 1985 · J. Nucl. Med.; (United States)

OSTI ID:7030919

Vallabhajosula, S; Ginsberg, H N; Badimon, J J; Brown, C; Lipszyc, H; Fuster, V; Goldsmith, S J

Radioiodinated low density lipoprotein (LDL) used for studying LDL kinetics is not suitable for nuclear scintigraphy. /sup 99m/Tc-LDL, (Tc-LDL) with ideal physical imaging characteristics is being evaluated for the noninvasive identification of atherosclerotic lesions. LDL was labeled with Tc-99m and purified by gel chromatography (labeling efficiency 28 +- 8%). Human LDL labeled with Tc-99m and I-131 were injected simultaneously into a normal cynomolgus monkey. The plasma decay curves of the two tracers were identical (T1/2:4.5hrs) indicating that Tc-LDL is stable in plasma and is similar to /sup 131/I-LDL. Gamma camera images obtained at 30 min post injection showed that 40% of the activity of both tracers was in the liver. Over the next 4-8 hours, I-131 activity in the liver diminished and appeared in the lower abdomen and thyroid (representing deiodination) while Tc-99m activity in the liver remained stable indicating higher stability of Tc-LDL within hepatocytes. Tc-LDL (rabbit) was injected into normal rabbits and rabbits fed on an atherogenic 0.5% cholesterol diet for 3 months (ATR). 24 hour images showed significant uptake of Tc-LDL in the aorta of ART only. The isolated aorta from ATR showed Tc-LDL uptake in the lesions identified as ''fatty streaks'' by Sudan IV staining. These results suggest that Tc-LDL is stable in vivo and appears to be an efficient agent to identify sites of normal catabolism of LDL as well as uptake of LDL by fatty vascular lesions.

• Research Organization: Mt. Sinai Medical Center, New York, NY
• OSTI ID: 7030919
• Report Number(s): CONF-850611-
• Conference Information: Journal Name: J. Nucl. Med.; (United States) Journal Volume: 26:5
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
ABDOMEN
ANIMALS
ARTERIES
ARTERIOSCLEROSIS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BLOOD CHEMISTRY
BLOOD VESSELS
BODY
BODY AREAS
CARDIOVASCULAR DISEASES
CARDIOVASCULAR SYSTEM
CATABOLISM
CHROMATOGRAPHY
COUNTING TECHNIQUES
DAYS LIVING RADIOISOTOPES
DECAY
DIAGNOSIS
DIAGNOSTIC USES
DIET
DIGESTIVE SYSTEM
DISEASES
DRUGS
ENDOCRINE GLANDS
EVALUATION
GEL PERMEATION CHROMATOGRAPHY
GLANDS
HOURS LIVING RADIOISOTOPES
IMAGE PROCESSING
IN VIVO
INTERMEDIATE MASS NUCLEI
IODINE 131
IODINE ISOTOPES
ISOMERIC TRANSITION ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
LABELLED COMPOUNDS
LABELLING
LIPIDS
LIPOPROTEINS
LIVER
MAMMALS
METABOLISM
MONITORING
MONKEYS
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANS
PRIMATES
PROCESSING
PROTEINS
PURIFICATION
RABBITS
RADIOISOTOPE SCANNING
RADIOISOTOPES
RADIOPHARMACEUTICALS
SEPARATION PROCESSES
TECHNETIUM 99
TECHNETIUM ISOTOPES
THYROID
TRACER TECHNIQUES
UPTAKE
USES
VASCULAR DISEASES
VERTEBRATES
YEARS LIVING RADIOISOTOPES