MMP2 and pulmonary arterial hypertension: MS-275 treatment decreased MMP-2/9 activity in MCT-treated PAH rats to 1.20-/1.10-fold over control (P < 0.05 versus MCT-treated group), and administration of miR-34a agomiR reduced MMP-2/9 activity in MCT-treated rats to 1.15-/1.04-fold over control (P < 0.05 versus MCT group).