Immunocytochemical (A) and immunoblot analyses (B) of hippocampal neurons infected with rAAVs containing expression cassettes for hrGFP, CREB or mCREB. CREB and mCREB contain triple Flag epitope tags and were detected with M2 Flag antibody; hrGFP was detected with an antibody to hrGFP. Cell nuclei were counterstained with Hoechst 33258. Representative images are shown. Scale bar, 10 μm.