MAPK3 and pulmonary arterial hypertension: The levels of p-AKT, AKT, p-ERK1/2, and ERK1/2 in Ctrl-PASMCs and MCT-PAH-PASMCs were compared by Western blot analysis at various time points after stimulation with 10% FBS for 0 min, 5 min, 15 min, 30 min, and 60 min.