Intratracheal injection of shRNA CF6 before or after MCT injection restored the maximal relaxation induced by ACh to 50.9 ± 4.5 % and 45.8 ± 6.4 % (p < 0.05 vs. MCT-control, Fig. 6), suggesting that CF6 inhibition exerts its beneficial effect by reducing endothelial dysfunction of the pulmonary artery rings in PAH rats. Here, ATP5PF is linked to pulmonary arterial hypertension.