CAPE inhibits MCT-induced HIF-1α expression and PDGF-BB production in rats. (A) Rats were treated with PBS or CAPE (5 or 10 mg/kg) from days 14–28 after MCT treatment 14 days (60 mg/kg). Preparation of lung tissues was analyzed by Western blot to determine the levels of HIF-1α protein. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH)was used as a loading control. (B) Serum levels of PDGF-BB in rat was assayed by an ELISA kit. (C) Representative images of immunohistochemical staining for HIF-1α in lung sections from the rats. Scale bars, 50 μm. (D) Immunofluorescence staining of alpha-smooth muscle actin (α-SMA) and HIF-1α in lung sections from rats. Scale bars, 50 μm. Data in (A,B) are expressed as mean ± SEM of three independent experiments. *** p < 0.01, as compared with the PBS group. ### p < 0.01, as compared with the rats exposed to MCT alone. Results are representative of three rats per experimental group.