Figure 3.

Time course and dose–response of induction for COX-2 protein by PGE₂ and PGE₃. NIH 3T3 fibroblasts were treated for 4 h with different concentrations of PGE₂ or PGE₃ (A), or with either PGE₂ (1 μg/ml) or PGE₃ (1 μg/ml) for different time periods (B). Total protein was harvested, and 15 μg per condition was subjected to Western blotting with anti-COX-2 antibody as described in Experimental Procedures.