Modulators of cigarette smoke-induced pulmonary emphysema in A/J mice.

Mice develop pulmonary emphysema after chronic exposure to cigarette smoke (CS). In this study, the influence of gender, exposure duration, and concentration of CS on emphysema, pulmonary function, inflammation, markers of toxicity, and matrix metalloproteinase (MMP) activity was examined in A/J mice. Mice were exposed to CS at either 100 or 250 mg total particulate material/m(3) (CS-100 or CS-250, respectively) for 10, 16, or 22 weeks.

Inhalation administration of all-trans-retinoic acid for treatment of elastase-induced pulmonary emphysema in Fischer 344 rats.

A past study demonstrated that all-trans-retinoic acid (ATRA) treatment by intraperitoneal injection in a rat model of elastase-induced emphysema caused tissue regeneration as evidenced by a decrease in alveolar size and lung volume and an increase in alveolar number. We postulated that treatment with this retinoid by nose-only inhalation exposure would be a more efficient means of targeting damaged lung tissue. Emphysema was induced in male Fischer 344 rats by intratracheal instillation of pancreatic elastase (0.