Estimation of in vivo reticuloendothelial system phagocytic activity in rats by direct blood clearance techniques and nuclear scintigraphy

Journal Article · Sun Jul 01 04:00:00 EDT 1990 · Journal of Leukocyte Biology; (USA)

OSTI ID:6642465

Goyal, D G; Gutowski, K A; Merion, R M ^[1]

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1. Univ. of Michigan Medical Center, Ann Arbor (USA)

There has been considerable interest in the examination of reticuloendothelial system phagocytic blockade. In this study, the kinetics of phospholipid liposome-mediated and intraperitoneal silica-mediated phagocytic blockade were examined using five methods of analysis of in vivo {sup 99m}Tc-labeled albumin clearance and reticuloendothelial cell uptake. Two direct blood sampling techniques revealed significant impairment in {sup 99m}Tc-labeled albumin clearance after treatment with silica (P less than 0.05), while liposome treatment was not associated with such impairment. A method utilizing nuclear scintigraphy for the determination of blood clearance was incapable of detecting silica-mediated blockade but demonstrated significant impairment by liposomes at 2 hr (P less than 0.001), 6 hr (P less than 0.05), and 24 hr (P less than 0.001). Gamma camera imaging methods for determination of hepatic uptake demonstrated significant (P less than 0.05) and reversible impairment of {sup 99m}Tc-labeled albumin uptake by liposomes. The most promising of these techniques utilizes deconvolutional analysis of liver region of interest time-activity curves to correct for continuously changing blood concentrations of tracer and for intracellular tracer processing and catabolism. Measurements of reticuloendothelial system phagocytic activity should include methods that take into account the observed discrepancies between blood clearance determinations and reticuloendothelial cell uptake.

• OSTI ID: 6642465
• Journal Information: Journal of Leukocyte Biology; (USA), Journal Name: Journal of Leukocyte Biology; (USA) Vol. 48:1; ISSN JLBIE; ISSN 0741-5400
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
ALBUMINS
ANIMAL TISSUES
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BLOOD-PLASMA CLEARANCE
BODY
CAMERAS
CELL CONSTITUENTS
CHALCOGENIDES
CLEARANCE
COUNTING TECHNIQUES
DIAGNOSTIC TECHNIQUES
DISTRIBUTION
DRUGS
GAMMA CAMERAS
HOURS LIVING RADIOISOTOPES
IN VIVO
INTERMEDIATE MASS NUCLEI
ISOMERIC NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPES
LABELLED COMPOUNDS
LIPOSOMES
MAMMALS
MINERALS
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANOIDS
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PHAGOCYTOSIS
PROTEINS
RADIOISOTOPE SCANNING
RADIOISOTOPES
RADIOPHARMACEUTICALS
RATS
RETICULOENDOTHELIAL SYSTEM
RODENTS
SCINTISCANNING
SILICA
SILICON COMPOUNDS
SILICON OXIDES
TECHNETIUM 99
TECHNETIUM ISOTOPES
TISSUE DISTRIBUTION
TISSUES
VERTEBRATES
YEARS LIVING RADIOISOTOPES