In order to investigate whether inhibition of the COX-2 enzyme activity had affected the tissue expression of cytoplasmic phospholipase A2 (cPLA2) and COX-2 proteins in the lungs from the pulmonary hypertensive SuHx rats, we extracted lung tissue protein and subjected the lysates to Western blotting. Here, PTGS2 is linked to pulmonary arterial hypertension.