Permeability of the bronchial mucosa to /sup 99m/Tc-DTPA in asthma

Journal Article · Mon May 01 04:00:00 EDT 1989 · Am. Rev. Respir. Dis.; (United States)

DOI:https://doi.org/10.1164/ajrccm/139.5.1139· OSTI ID:5902533

Ilowite, J S; Bennett, W D; Sheetz, M S; Groth, M L; Nierman, D M

Previous investigators, using 99mTc-DTPA aerosol as a marker to assess epithelial permeability in asthma, did not find an increased permeability in this group. However, they either failed to deliver the aerosol to the optimal site (bronchial mucosa, not alveoli) or failed to account for mucociliary clearance in analyzing their results. We studied 10 asthmatics and eight age-matched control subjects using a dosimeter (Spira-Elektra 2) and a carefully controlled breathing pattern to deliver aerosol to the subjects' airways. Two aerosols were delivered on separate days in each patient; 99mTc-DTPA aerosol, and 99mTc-HSA (human serum albumin), using similar breathing patterns to ensure reproducibility of the deposition pattern with the two aerosols. From measurements of retention versus time over a 1-h period, rate constants Ktot and Km were determined for the clearance of 99mTc-DTPA and 99mTc-HSA, respectively. By modelling the airways as a single compartment with two possible routes of clearance, we determined the permeability rate constant, Kp, as Ktot minus Km. There was no significant difference between Ktot in normal subjects and asthmatics; however, because of the slower mucociliary clearance in the asthmatic group, and the relative importance of mucociliary clearance in determining the washout of 99mTc-DTPA aerosol, there was a significant difference in airway permeability between the normal subjects and the asthmatics (t1/2 = 296 min +/- 141 SD and 126 min +/- 58, p less than 0.01, in normal subjects and asthmatics, respectively).

• Research Organization: St. Luke's/Roosevelt Hospital Center, New York, NY (USA)
• OSTI ID: 5902533
• Journal Information: Am. Rev. Respir. Dis.; (United States), Journal Name: Am. Rev. Respir. Dis.; (United States) Vol. 139:5; ISSN ARDSB
• Country of Publication: United States
• Language: English

Related Subjects

550901* -- Pathology-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ABSORPTION
AEROSOLS
ALBUMINS
AMINO ACIDS
ANIMAL TISSUES
ANIMALS
ASTHMA
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BODY
BRONCHI
CARBOXYLIC ACIDS
CELL CONSTITUENTS
CELL MEMBRANES
CHELATING AGENTS
CLEARANCE
COLLOIDS
DISEASES
DISPERSIONS
DRUGS
DTPA
EPITHELIUM
EXCRETION
HOURS LIVING RADIOISOTOPES
INTERMEDIATE MASS NUCLEI
ISOMERIC NUCLEI
ISOMERIC TRANSITION ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
LUNG CLEARANCE
MAMMALS
MAN
MEMBRANES
MUCOUS MEMBRANES
NUCLEI
ODD-EVEN NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
PATHOGENESIS
PERMEABILITY
PRIMATES
PROTEINS
RADIOISOTOPES
RADIOPROTECTIVE SUBSTANCES
RESPIRATORY SYSTEM
RESPIRATORY SYSTEM DISEASES
SOLS
TECHNETIUM 99
TECHNETIUM ISOTOPES
TISSUES
TRACER TECHNIQUES
VERTEBRATES
YEARS LIVING RADIOISOTOPES