Cathepsin L inhibition by short hairpin RNA (shRNA) can attenuate PAH in MCT- and Su/Hx-induced rats by restoring BMPR2 expression.64 Isorhamnetin reduces inflammatory factors and improves BMPR2 signaling in MCT-PAH rats.396 Overall, normal BMPR2 expression is vital for pulmonary vascular health, and its deficiency promotes PH progression through inflammation and cellular changes. Here, BMPR2 is linked to pulmonary arterial hypertension.