ACTA1 and pulmonary arterial hypertension: To further explore the effect of EndMT on the pathological mechanism of pulmonary hypertension, WB experiments were performed, which revealed that the expression of α-SMA, vimentin, (mesenchymal markers), Twist1, snail and slug (endothelial to mesenchymal transition markers) was significantly increased in the lung tissue of MCT-induced pulmonary hypertension rats, but the absence of eIF3a reversed these changes.