Lung function and morphology of dogs after sublethal exposure to nitrogen dioxide.
The relationship between respiratory function and morphological changes in 10 dogs exposed for 6 h to 69 ppm nitrogen dioxide was studied. Two additional dogs served as controls. Functional assessments included breathing pattern, breathing mechanics, forced expiration, gas exchange, and acid-base status. Gross, microscopic, and ultrastructural evaluations were made of lung tissues from dogs killed at 0.1, 1.0, 2.0, 3.0, 7.0 and 14.0 d after exposure. Functional changes were similar to those reported for man. The principal dysfunction was gas-exchange impairment, apparently resulting from foam in the airways. Breathing-pattern alterations appeared to result from stimulation of neural receptors. Gas-exchange measurements provided the most useful indicators of the pulmonary damage observed in this study.
D000818:Animals; D001784:Blood Gas Analysis; D002245:Carbon Dioxide / Q000378:metabolism; D004285:Dogs; D006863:Hydrogen-Ion Concentration; D008168:Lung / Q000187:drug effects* / Q000473:pathology; D008297:Male; D009585:Nitrogen Dioxide / Q000633:toxicity*; D012129:Respiratory Function Tests; D013997:Time Factors
D002245:Carbon Dioxide; D009585:Nitrogen Dioxide