To explore the role of eIF3a in the development of pulmonary hypertension in MCT-induced PAH rats, a rat model of pulmonary hypertension was generated via the intraperitoneal injection of MCT, and both WB and immunohistochemistry revealed that eIF3a expression in the lung tissue was significantly greater in MCT-induced pulmonary hypertension rats than in control rats. This evidence concerns the gene EIF3A and pulmonary hypertension.