Figure 2.

Myocardial fibrosis in MCT-induced PAH animal model. (A,B) Interstitial and perivascular collagen deposition in the transverse cardiac section was examined by Masson’s trichrome staining. Collagen fibers are indicated in blue. (C,D) Interstitial and perivascular collagen fiber accumulation in cardiac tissue was determined and quantified by transmission electron microscopy (TEM). Collagen fibers are indicated with blue arrows. (E,F) Cardiac collagen deposition and arrangement from the endocardium to epicardium were identified and quantified by second-harmonic generation (SHG) microscopy. Data are representative of three independent experiments (n = 3), and values are expressed as median and interquartile range. Mann–Whitney U-test was used to compare two independent groups (** p < 0.01).