Fig. 5

Inhibition of histone deacetylases 1 (HDAC1) reduces the ratio of matrix metalloproteinase 9 (MMP-9)/tissue inhibitor of metalloproteinase 1 (TIMP-1) and MMP-2/TIMP-2 and the expression of collagen I through restoring miR-34a level in monocrotaline (MCT)-induced pulmonary arterial hypertension (PAH) rats. a miR-34a level in lung tissues from different groups was determined using quantitative real-time polymerase chain reaction (qRT-PCR) (n = 3). b MMP-2/9 activity in lung tissues from different groups was measured using gelatin zymography (n = 3). c Protein level of TIMP-1 and TIMP-2 in lung tissues from different groups was examined using immunoblotting (n = 3). d Ratio of MMP-9/TIMP-1 and MMP2/TIMP-2 was analyzed in lung tissues from different groups (n = 3). e Collagen I production in lung tissues from different groups was determined using enzyme-linked immunosorbent assay (ELISA) (n = 3). *P < 0.05 versus control group; ^#P < 0.05 versus MCT group