Figure 1. Concentration-dependent
inhibition by 17β-estradiol and progesterone of IL-1β–induced
collagen degradation by corneal fibroblasts. Cells were cultured
in collagen gels with (white bars) or without (gray bars) IL-1β
(0.1 ng/ml) and in the presence of the indicated concentrations
of 17β-estradiol or progesterone for 36 h, after which the
amount of degraded collagen was determined. Data are expressed
as micrograms of hydroxyproline (HYP) per well and are means±SEM
of quadruplicates from an experiment that was repeated three
times with similar results. *p<0.05 (Dunnett’s test) versus
the corresponding value for cells cultured without female sex
hormones.