Figure 4. Modulation of cyclo-oxygenase-2 (COX-2) expression in human intestinal microvascular endothelial cells (HIMECs) by mitogen-activated protein kinase (MAPK) inhibitors. (A and B) Inhibition of the MAPK pathways resulted in downregulation and suppression of COX-2 mRNA and protein. Pretreatment of HIMECs with either 10 µM PD098059 (p44/42 MAPK), 5 µM SB203580 (p38 MAPK) or 10 µM SP600125 (Jun N-terminal kinase) significantly inhibited vascular endothelial growth factor (VEGF)-induced COX-2 mRNA and protein expression. (C) All three MAPK inhibitors inhibited prostaglandin E₂ (PGE₂) production as determined by ELISA in HIMEC culture media. *p <0.05 for inhibitors vs VEGF.