Figure 1. Effects of RAR agonists on TGF-β1-induced collagen gel contraction mediated by HTFs. Cells were incubated in collagen gels
first for 12 h in the absence or presence of 1 µM Am580, BmS453, or R667 and then for 3 days in the additional absence or
presence of transforming growth factor-β1 (TGF-β1; 1 ng/ml), after which the change in gel diameter was measured. The extent
of TGF-β1-induced gel contraction was 5.17±0.29, 3.73±0.25, 4.67±0.29, and 2.27±0.25 mm in the absence or presence of Am580,
BmS453, or R667, respectively. Data are means ± standard deviation (SD) from three independent experiments. *p<0.01 versus
the corresponding value for cells cultured with TGF-β1 alone (the Tukey-Kramer test).