Fig. 6

PFD ameliorates bleomycin-induced pulmonary fibrosis in RGS2+/+ but RGS2−/− mice. a Outline of experimental design. Bleomycin (1.5 U/kg body weight) was administrated intratracheally on Day 1. Mice were divided into four groups (4 mice/group): bleomycin in RGS2+/+, bleomycin + PFD in RGS2+/+, bleomycin in RGS2−/−, bleomycin + PFD in RGS2-/-. Treatment with PFD was started 1 week later and continued for 2 weeks. All mice received daily 20-min exposures to nebulized PFD solution or saline vehicle via a nose-only aerosolized delivery system. On Day 22, mice were tested in functional assays. b Representative western blot of RGS2 protein expression in lung homogenates of RGS2+/+ and RGS2−/− mice without or with PFD treatment. c C_dyn was measured using a Buxco FinePointe system. d The lungs were stained with trichrome to visualize collagen deposition (blue). Representative sections from each group are shown. e Sections were scored by the Ashcroft method for overall fibrosis (scale bar = 200 μm). f Total lung collagen content was measured by the Sirius red collagen assay. Results are expressed as μg of collagen per 100 mg of lung tissue. Data are means ± SEM (n = 4 mice). * p < 0.01, NS: not significant