The effect of lipopolysaccharide (LPS) and Pyl A on myometrial and pup brain nuclear factor-κB (NF-κB) and cyclo-oxygenase 2 (COX 2). Dams were killed at 4.5 hr post intrauterine injection and tissue was harvested for protein analysis of phospho-p65 and COX-2 (n = 3). Co-injection of LPS and Pyl A increased myometrial phospho p65 (a), with no effect on pup brain phospho-p65. Phospho-p65 was decreased in brains of pups from dams treated with LPS alone (b). Representative phospho-p65 immunoblots are shown for each treatment group with B actin used as a loading control. No significant changes in COX-2 protein expression were seen in any treatment group in both myometrium and pup brain (c,d). However, an increase in messenger RNA of COX-2 was seen in LPS-treated and LPS/Pyl A-treated mice (e). For statistical analysis, one-way analysis of variance with Bonferroni's multiple comparison test was used; *P < 0.05, ***P < 0.001.