Chrysin attenuated collagen expressions in pulmonary arteries from rats with hypoxia -induced PH. (A, C) The expressions of collagen I and collagen III mRNAs were determined by real-time PCR. (B, D) The expressions of collagen I and collagen III proteins were determined by western blotting. (E) Masson’s trichrome staining of lung tissues. (F) Collagen volume fraction (CVF) values of lung tissues. (G) Perivascular collagen area (PVCA) values. Data are means ± SD (n = 8 rats per group). Statistical analysis was performed with one-way ANOVA followed by the Newman–Student–Keuls test for multiple comparisons.