Figure 1

ET-1 induced COX-2 expression and PGE ₂ release. (A) Time and concentration dependence of ET-1-induced COX-2 expression, cells were treated with various concentration ET-1 for the indicated time intervals. (B) Time dependence of ET-1-induced COX-2 mRNA expression, cells were treated with 10 nM ET-1 for the indicated time intervals. COX-2 mRNA was analyzed by RT-PCR. (C) Time dependence of ET-1-induced COX-2 promoter transcription activity, cells were transfected a COX-2 promoter–luciferase reporter gene and then incubated with ET-1 for the indicated times. The promoter reporter assay was performed as described in “Materials and Methods”. (D) PGE₂ release induced by ET-1, the conditioned media were collected to assay PGE₂ level by EIA as described in “Materials and Methods” (n=3 in each group; ^*P<0.05, ^#P<0.01 compared with vehicle).