MMP12 and pulmonary fibrosis: Correlations between MRI and all other readouts on day 23 analyzed in the present study for detection of bleomycin-induced lung fibrosis in BALB/c mice (n = 32; except for Picrosirius n = 16): total MRI signal volume, picrosirius staining, hydroxyproline, and gene expression of Col1α1, F4/80 and MMP12.