title: Acute and chronic effects of marijuana smoking on pulmonary alveolar permeability.
abstract: Pulmonary clearance of technetium (99mTc)-labeled diethylene triamine pentaacetate (DTPA), a sensitive test of alveolar epithelial permeability, was measured twice in 34 healthy subjects, including 10 control nonsmokers (NS), 10 habitual smokers of marijuana alone (MS) (> or = 10 joints/wk), 9 regular smokers of tobacco alone (TS) (> or = 15 cigarettes/day) and 4 habitual smokers of both marijuana and tobacco (MTS). In smokers, the first study was performed after > or = 12 hrs of abstinence from smoking to assess chronic effects of marijuana and/or tobacco smoking on alveolar permeability; the second study was performed within 15 min of smoking to assess possible acute effects. TS exhibited abnormally rapid 99mTc-DTPA clearance after > or = 12 hours of abstinence, indicating an increase in pulmonary epithelial permeability, consistent with chronic tobacco-induced lung injury. MS showed a more modest and less consistent chronic effect than TS on 99mTc-DTPA clearance, suggesting a more variable and smaller degree of marijuana-induced lung injury. No acute effect of tobacco or marijuana smoking on 99mTc-DTPA clearance was apparent. Concomitant habitual smoking of marijuana and tobacco had no additive effect on alveolar permeability.
authors.affiliation: Department of Medicine, UCLA School of Medicine 90095, USA.
authors.forename: E
authors.initials: E
authors.lastname: Gil
authors.forename: B
authors.initials: B
authors.lastname: Chen
authors.forename: E
authors.initials: E
authors.lastname: Kleerup
authors.forename: M
authors.initials: M
authors.lastname: Webber
authors.forename: D P
authors.initials: DP
authors.lastname: Tashkin
mesh_terms: D000328:Adult; D002463:Cell Membrane Permeability; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008385:Marijuana Smoking / Q000009:adverse effects* / Q000378:metabolism / Q000473:pathology; D010947:Plants, Toxic; D011650:Pulmonary Alveoli / Q000378:metabolism* / Q000473:pathology; D012907:Smoking / Q000009:adverse effects / Q000378:metabolism / Q000473:pathology; D016284:Technetium Tc 99m Pentetate / Q000493:pharmacokinetics; D014026:Nicotiana
chemical_list: D016284:Technetium Tc 99m Pentetate