Chronic inhalation of marijuana and tobacco in dogs: pulmonary pathology
Roy, P.E.; Magnan-Lapointe, F.; Huy, N.D.; Boutet, M.
Research Communications in Chemical Pathology and Pharmacology 14(2): 305-317
1976
ISSN/ISBN: 0034-5164 PMID: 940962 Document Number: 99257
The pulmonary effects of chronic marihuana (M) and tobacco (T) smoke inhalation were studied in adult female dogs. The smoke was inhaled through a tracheostomy tube: 4 cigarettes containing either tobacco (3.2 g/dog) or marihuana (3.0 g/dog) were used per day over 900 days. At autopsy, the pulmonary volume and alevolar surface of the T group had decreased, compared to controls (C) and the M group. The tracheostomy (Tr) procedure resulted in a decreased alveolar surface and a high incidence of bronchiolitis; in order of severity the M group > T > Tr > C. The incidence of squamous metaplasia also followed this order but the T group showed more abnormalities affecting the mucosal membrane. Chronic inhalation of marihuana and tobacco produced bronchiolitis with macrophage infiltration in the wall of the terminal air-passages. This may induce the pulmonary emphysema.