(E) Schematic of experimental protocol. Animals were divided into 4 groups: control (Ctrl), pulmonary fibrosis (PF), pulmonary hypertension (PH) and PF secondary to PH (PF-PH). At day 0, rats in PF and PF-PH groups received an intra-tracheal instillation of Bleomycin (2.5mg/Kg), whereas Ctrl and PH groups received a PBS instillation. At day 14, PH and PF-PH groups received a subcutaneous injection of monocrotaline (MCT, 60mg/kg), whereas Ctrl and PF groups received a subcutaneous injection of PBS. 