Figure 6.

Involvement of PI-PLC in eotaxin-1-induced MMP-3 secretion in human chondrosarcoma cells. (A) SW1353 cells were treated with various concentrations of eotaxin-1 for 30 min, and determined IP₃ level by IP₃ [³H] radioreceptor assay. (B) SW1353 cell were treated for 4 h with IL-1β (1 ng/ml) followed by 1 h with actinomycin D (5 μg/ml) and various inhibitors as follows: PI-PLC inhibitor U73122 (5, 10 or 20 μM), calcium inhibitor Bapta-AM (Bapta; 5, 10 or 20 μM), PKC inhibitor chelery chloride (Chelery; 0.5, 1 or 2 μM), or adenylate cyclase inhibitor 2',5'-dideoxyadenosine (ACi; 100, 250 and 500 μM). The cells were then treated with eotaxin-1 (100 ng/ml) for 4 h. MMP-3 protein secreted in culture media was determined by Western blotting and quantified. The values in the plots were the mean of at least three assays. * p < 0.05.