Elevated levels of secreting prostaglandins derived from Cox2 after BMP6 stimulation. MECs were pretreated with NS398 (10 μM), SC560 (100 nM), or vehicle before BMP6 (100 ng/mL) treatment. Cox2-dependent prostanoid generation was determined by measurement of the major forms of PGs generated by ECs, PGE₂ (A), and 6-keto-PGF_1α (B) after 4 hours of stimulation in the presence of exogenous arachidonic acid (2.5 μM). Data are expressed as means ± SEM of 6 replicates. *P < .001 compared with control.