Fig. 5.
Activation of collagen-degrading enzymes in the liver during fibrosis reversal. A: gelatin gel zymography of representative liver homogenates demonstrates that MMP-9 is the most prominent gelatinase, reaching highest levels at the peak of fibrolysis (week 4 of reversal), whereas MMP-2 declines. Densitometry of the MMP-9 band was performed from zymographies of all livers (n = 4–6 per bar) and is expressed as arbitrary units relative to the sham-operated controls (means ± SE). B: corresponding changes in MMP-9 protein as detected by Western blotting in representative liver homogenates. C: expression of MMPs and components of the plasmin proteolytic system during fibrosis reversal. Transcript levels of MMPs, urokinase plasminogen activator (uPA) and uPA receptor (UPAR)-1 were quantified by quantitative RT-PCR. Data are expressed as means ± SE and in arbitrary units relative to β2MG mRNA. *P < 0.05 compared with the sham-operated group; +P < 0.05 compared with the peak fibrosis group (BDL).