A: UAEC transiently transfected with the 1305-kb sheep NOS3 promoter-luciferase reporter, wild type (wt-AP-1) or proximal AP-1 mutant (mt-AP-1), as described in Fig. 10. After treated with 20 nM PMA for 24 hr, luciferase activity was determined as described in Fig. 9. B: UAEC were treated with increase concentrations of PMA for 24 hr, total protein lysates were prepared and protein levels of NOS3, c-Jun, and β-actin were measured by immunoblotting with their respective specific antibody. Results represent data (mean ± SEM) from four independent experiments using cells from different ewes. Bars with different superscripts differ significantly (p<0.05). * p<0.05 vs. controls in panel B.