[Gene expression of interstitial collagenase MMP-13 in progressive phase of rat liver fibrosis induced by ethanol].

OBJECTIVES: To demonstrate the gene expression of MMP-13 in the progressive phase of ethanol-induced experimental liver fibrosis in rats. METHODS: 34 SD rats were randomized into two groups. The rats in experimental group (n=24) were given ethanol (44%, 7g/kg) every day, and the rats in control group (n=10) were given equality normal saline. Liver samples were harvested from experimental rats at the 4th, 12th and 24th weeks respectively. The dynamic expression of MMP-13 mRNA was assayed by semi-quantity reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: In normal rat liver, a faint band of MMP-13 mRNA was observed by RT-PCR (0.24+/-0.41). The gene expression of MMP-13 increased in the livers of rats treated with ethanol for 4 weeks (0.62+/-0.54), but it was not considered statistically, when compared with that in normal rats livers. And the livers from 12-week-treated rats showed a markedly MMP-13 mRNA expression (1.65+/-0.47, t=-4.363, P<0.01). Once the fibrosis became prominent (24 weeks), a faint band of MMP-13 mRNA was observed (0.39+/-0.25). CONCLUSION: MMP-13 participates in the degradation of newly-formed matrix in the early phase of rat liver fibrosis induced by ethanol, but it expresses in a distinct time frame