Figure 3.

cAMP-response element binding protein (CREB) small interfering RNA (siRNA) treatment blocked lipopolysaccharide (LPS) or PMA-elicited CREB activation, cyclooxygenase-2 (COX-2) expression and prostaglandin E₂ (PGE₂) production. (a, b) CREB mRNA and protein expression were analysed in siRNA-pre-treated rat peritoneal macrophage by quantitative PCR and immunoblotting. (c) The effect of LPS or PMA on the expression and phosphorylation of CREB was also measured by immunoblotting in siRNA-pre-treated macrophages. Meanwhile, the protein (d) and mRNA (e) expression of COX-2 and the production of PGE₂ (f) were also assessed in these macrophages.