Tracheobronchial clearance studies in the guinea pig

Technical Report · Thu Jan 01 04:00:00 EST 1981

OSTI ID:6568719

Velasquez, D J

Tracheobronchial clearance in guinea pigs exposed to relatively monodisperse aerosols was studied. Two new techniques were developed which enabled tagging of polystyrene particles with /sup 198/Au and with a fluorescent dye. A procedure was also developed to generate polystyrene particles with a vibrating orifice generator. Seventy animals were exposed via inhalation to relatively monodisperse polystyrene aerosols. Following exposure, animals were radioactively counted at regular intervals, sacrificed at predetermined times, and the lungs were removed, inflated to a standard pressure, frozen in liquid nitrogen, and freeze-dried. The freeze-dried lungs were sectioned completely, examined with a fluorescent microscope, and measurements were made of airway diameters in which particles were found. The results indicated a significant penetration of particles to the distal bronchioles and air spaces for 7.9 ..mu..m (MMD) particles and a lesser, though still significant, penetration for 10.3 ..mu..m (MMD) particles. An anatomical model for guinea pig lung morphology was used to classify particular ranges of airway diameters into zones. These zones were used to specify a compartmental model for lung clearance and the experimental particle distributions were categorized using this model. Equations were then developed describing the compartmental clearance. Rate constants were then obtained and used to predict airway transport rates in specific lung generations.The predicted transport rates ranged from approximately 0.001 mm/min in the distal bronchioles to approximately 8 mm/min in the trachea. These values agree with previous models for airway transport rates, and are consistent with experimental determinations of tracheal transport rates. Transit times were calculated and the results indicate a 24 hr clearance time for tracheobronchial clearance in the guinea pig. (ERB)

• Research Organization: Rochester Univ., NY (USA). Dept. of Radiation Biology and Biophysics
• DOE Contract Number: AC02-76EV03490
• OSTI ID: 6568719
• Report Number(s): UR-3490-1981
• Country of Publication: United States
• Language: English

Related Subjects

560172* -- Radiation Effects-- Nuclide Kinetics & Toxicology-- Animals-- (-1987)
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63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AEROSOL GENERATORS
AEROSOLS
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BRONCHI
CLEARANCE
COLLOIDS
COMPARTMENTS
DAYS LIVING RADIOISOTOPES
DISPERSIONS
DYES
EXCRETION
FLUORESCENCE
GOLD 198
GOLD ISOTOPES
GUINEA PIGS
HEAVY NUCLEI
INHALATION
INTAKE
ISOTOPES
LABELLED COMPOUNDS
LUMINESCENCE
LUNG CLEARANCE
MAMMALS
MATERIALS
MATHEMATICAL MODELS
NUCLEI
ODD-ODD NUCLEI
ORGANIC COMPOUNDS
ORGANIC POLYMERS
PETROCHEMICALS
PETROLEUM PRODUCTS
PLASTICS
POLYMERS
POLYOLEFINS
POLYSTYRENE
POLYVINYLS
RADIOACTIVE AEROSOLS
RADIOISOTOPES
RESPIRATORY SYSTEM
RODENTS
SOLS
SYNTHETIC MATERIALS
TRACHEA
VERTEBRATES