Figure 6. The effects of cyclooxygenase (COX) inhibitors on total PG release from human ciliary muscle (h-CM) cells. Concentration-dependent effects of flurbiprofen and bromfenac on their own on PG secretion was studied along with the positive control agent BK. Both COX inhibitors inhibited the background level of total PGs released from h-CM cells in an apparent concentration-dependent manner up to 100 nM, whereas BK (1 µM) substantially increased the PGs secreted above the basal levels (Figure 6A; data from a single experiment). Pretreatment of h-CM cells with various concentrations of the COX inhibitors before challenge with 1 µM BK resulted in a concentration-dependent reduction in total PGs synthesized and secreted, with flurbiprofen much more potent than bromfenac (Figure 6B). Data are mean ± SEM from three experiments for each inhibitor (Figure 6B).