Figure 4: p,p-DDE exposure increases C/EBPβ protein levels in the nuclei in a concentration-dependent manner mediated by p38 kinase. (a) C/EBPβ nuclear protein levels were assessed after 12 h of exposure to 0.019, 0.19, or 1.9 μg/mL of p,p-DDE. (b) C/EBPβ nuclear protein levels after 12 h of exposure to 1.9 μg/mL of p,p′-DDE alone or with iERK (ERK inhibitor, PD98058), iJNK (JNK inhibitor SP600125), or ip38 (p38 inhibitor, SD203508). Inhibitors were added 30 min before exposure to p,p-DDE. Densitometric values were normalized to histone 4 protein levels. Data from three independent experiments are expressed as mean ± SEM. indicates differences relative to the control and indicates differences relative to treatment with 1.9 μg/mL of p,p-DDE. Data were analysed using one-way ANOVA followed by Dunnett’s post hoc test.