Figure 1. Chronic treatment with nicotine and/or 24hWD significantly increases phosphorylation of CREB in the hippocampus and increases CREB binding to the promoter for Nrg3.
Animals were treated in vivo with either saline, nicotine (18 mg/kg/day), or undergoing 24h withdrawal (WD) from nicotine. Hippocampal tissues from treated animals were used in A) Western blot analysis to evaluate phosphorylation levels of CREB as well as in B) ChIP analysis to evaluate binding to the promoter for Nrg3. A) Both chronic nicotine as well as 24h WD from chronic nicotine elicited significant increases in pCREB relative to saline in wildtype (WT) animals. No change was observed in CREB mutant mice, which exhibit a 90% reduction in total CREB levels (N=4–5). Representative blots are shown below panel A. B) CREB binding to Nrg3 was significantly increased following chronic treatment with nicotine (18 mg/kg/day) (N=6–7). *, p<0.05; **, p<0.01.