In vivo distribution and excretion studies and in vitro blood studies on the kinetics of lead-203 in beagle dogs

Thesis/Dissertation · Tue Jan 01 00:00:00 EST 1980

DOI:https://doi.org/10.2172/6564204· OSTI ID:6564204

Coombs, Mark A. ^[1]

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1. Rochester Univ., NY (United States). Dept. of Radiation Biology and Biophysics

The distribution of carrier free lead-203 between plasma and cells of canine blood in vitro was measured. Activity in the plasma decreased to less than 5% of the initial blood activity during the first 15 min and then exponentially with a half time of 160 min. Incubation in cell free plasma before addition to whole blood transformed the isotope, decreasing the amount subsequently associated with cells. In animal studies, activity was measured in plasma, blood cells, urine, and feces after exposure to lead-203. In one group, the animals were exposed by intravenous injection of dilute citric acid solutions of isotope. In a second group, carrier free isotope which had been transformed by incubation in plasma was injected intravenously. The kinetics of the distribution of the isotope differed between the two experimental groups. After injection of the transformed lead, the lead-203 content of the blood cell fraction rose from 10% of the dose at 5 min to 21% to 43% at 13 h. The red cell activity after injection of citric acid solutions of lead-203 remained between 50 and 60% of the dose from 5 min to 12 h post exposure. Excretion of lead in the urine during the first day after injection of transformed lead ranged from 5 to 45% of the dose, while that of citric acid solutions of lead was between 1 and 2%. Linear compartmental models for distribution of the isotope were developed for both in vitro and in vivo experimental systems. In three additional experiments, animals were exposed to lead-203 extravascularly. In one, using a dilute citric acid solution of the isotope, plasma activity resembled that observed after intravenous injection, suggesting that isotope was transformed by extravascular fluids before reaching the circulation. In the two remaining experiments the animals were exposed to lead-203 by gavage. The results suggest that lead absorbed from the gut may have been transformed before reaching the circulation. (ERB)

• Research Organization: Rochester Univ., NY (United States). Dept. of Radiation Biology and Biophysics
• Sponsoring Organization: USDOE; US Energy Research and Development Administration (ERDA)
• DOE Contract Number: AC02-76EV03490
• OSTI ID: 6564204
• Report Number(s): UR-3490-1883
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
59 BASIC BIOLOGICAL SCIENCES
BEAGLES
RADIONUCLIDE KINETICS
BLOOD PLASMA
ERYTHROCYTES
LEAD 203
EXCRETION
TISSUE DISTRIBUTION
CARRIER-FREE ISOTOPES
COMPARATIVE EVALUATIONS
IN VITRO
IN VIVO
INCUBATION
INTRAVENOUS INJECTION
MATHEMATICAL MODELS
ORAL ADMINISTRATION
SUBCUTANEOUS INJECTION
TRACER TECHNIQUES
ANIMALS
BETA DECAY RADIOISOTOPES
BIOLOGICAL MATERIALS
BLOOD
BLOOD CELLS
BODY FLUIDS
CLEARANCE
DAYS LIVING RADIOISOTOPES
DISTRIBUTION
DOGS
ELECTRON CAPTURE RADIOISOTOPES
EVEN-ODD NUCLEI
HEAVY NUCLEI
INJECTION
INTAKE
ISOMERIC TRANSITION ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
LEAD ISOTOPES
MAMMALS
MATERIALS
NUCLEI
RADIOISOTOPES
SECONDS LIVING RADIOISOTOPES
VERTEBRATES
560305* - Chemicals Metabolism & Toxicology- Vertebrates- (-1987)
551001 - Physiological Systems- Tracer Techniques