Figure 6.

Signaling cascades regulating S1P-induced S1P-production and S1P-induced activation of NF-κB. A. NF-κB-activation induced after stimulating HeLa cells for 30 minutes with 3 μM S1P. The cells were pre-treated with 10 μM BAPTA-AM for 30 minutes, 50 μM PD98059 for 30 min, 1 μM GF109203× for 5 min or 30 nM Wortmannin for 5 minutes. B. The cells were treated with inhibitors the same way as in A. Following a 10-minute stimulation with 3 μM S1P or vehicle together with [³H]sphingosine, lipids were extracted and the produced [³H]S1P was measured by thin layer chromatography and scintillation counting. The bars in A and B denote the mean ± SEM of at least three independent experiments (*, p < 0.05).