Abstract: BACKGROUND AND AIM: To study the changes of peroxisome proliferator-activated receptor γ (PPAR-γ) expressions at different time points in rat lung after phosgene exposure and explore the role of PPAR-γ in this pathogenesis. MATERIALS AND METHODS: 60 male rats were randomly divided into 6 groups with 10 in each group. The six groups were: negative group exposed to room air and the positive groups exposed to 38.08 mg/L phosgene for 1 minute. The five positive groups of rats were exposed to phosgene in the same dose and same time, but rats were killed 1,3,6,12 and 24 hours after exposure. The expressions of PPAR-γ mRNA and TNF-α mRNA in lung were measured by RT-PCR, PPAR-γ protein by Western-blot, and the TNF-α content by ELISA. RESULTS: With prolonged time after phosgene poisoning, compared with control rats, W∶D lung weight ratio significantly increased (P<0.05). The expression of lung TNF-α mRNA increased markedly(P<0.05). PPAR-γ mRNA expression in lung decreased at 1 h after phosgene exposure, and declined to the lowest level at 3 h after exposure. PPAR-γ protein in lung significantly decreased in positive groups, declined to its lowest point in 3 h, then gradually increased(P<0.05). CONCLUSION: Expressions of PPAR-γ mRNA and its protein in lung were decreased significantly after phosgene exposure. This may be related to the inflammation induced by phosgene.

Key words: phosgene, pulmonary edema, tumor necrosis factor α, peroxisome proliferator-activated receptor γ