The mechanism underlying the worsening clinical phenotype of PAH with Bmpr2 mutations has been largely unaddressed in rat models of pulmonary hypertension (PH) because of the difficulty in reproducing progressive PH in mice and genetic modification in rats. We tested whether a clinically-relevant Bmpr2 mutation affects the progressive features of monocrotaline (MCT) induced-PH in rats. The gene discussed is BMPR2; the disease is pulmonary hypertension.