Figure 4. Effects of 17β-estradiol on MMP abundance and activity in culture supernatants of corneal fibroblasts stimulated with IL-1β. Cells were cultured in collagen gels in the presence of IL-1β (0.1 ng/ml) and the indicated concentrations of 17β-estradiol for 36 h, after which the culture supernatants were subjected to immunoblot analysis with antibodies to MMP-1 or to MMP-3 (A) or were analyzed by gelatin zymography (B). Bands corresponding to the pro and active forms of MMPs are indicated. Similar results were obtained in three separate experiments.