Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Lung clearance of inhaled /sup 99m/Tc-DTPA in the dog

Journal Article · · J. Appl. Physiol.: Respir., Environ. Exercise Physiol.; (United States)
OSTI ID:5446268

A study was made of the reproducibility of measuring an index of permeability of respiratory epithelium in dogs using aerosolized /sup 99m/Tc-DTPA (diethylenetriaminepentaacetate). The method uses a gamma camera to measure the rate of clearance of soluble radioactive aerosol deposited in the lung. A solution of /sup 99m/Tc-DTPA in normal saline was aerosolized by an ultrasonic nebulizer. Eleven anesthetized dogs breathing spontaneously inhaled the resulting droplets for 2 min. Mass median aerodynamic diameter of the droplets was 4.4 ..mu..m with a geometric standard deviation of 2.1. Clearance from the lung was monitored by quantitative gamma camera imaging for up to 2 h. For a 60-min observation period, the biological half-life for clearance of /sup 99m/Tc-DTPA from both lungs was 66 +/- 11 (SD) min. Apical regions cleared significantly slower than basal regions, probably because of a larger portion of bronchial tissue in the apical region of the dog's lung. The best reproducibility of absorption of /sup 99m/Tc-DTPA in the dog was obtained from basal regions and peripheral zones of the lung within 30 min after inhalation of the radioaerosol.

Research Organization:
Univ. of Rochester School of Medicine and Dentistry, NY
DOE Contract Number:
AC02-76EV03490
OSTI ID:
5446268
Journal Information:
J. Appl. Physiol.: Respir., Environ. Exercise Physiol.; (United States), Journal Name: J. Appl. Physiol.: Respir., Environ. Exercise Physiol.; (United States) Vol. 57:2; ISSN JARPD
Country of Publication:
United States
Language:
English