Effects of PPARα activation with clofibrate (10 μM) for 18 h on PMA (1 μM)-, BK (1 μM)-, AII (1 μM)-, or Hem (10 μM)-induced ET-1 production by CMVEC. Following PPARα activation with clofibrate, cells were washed and incubated with PMA, BK, AII, or Hem for 4 h. At the end of the incubation, media and cells were collected for ET-1 level and protein determination, respectively. Results are expressed as femtomoles per microgram of protein and presented as mean ± S.E.M. (*, compared with control; #, compared with clofibrate, PMA, BK, AII, or Hem alone; p < 0.05, n = 6, ANOVA).