(B) In coronal brain sections of mice positive for both transgenes (TgCN12-itTA and TgOCN1) β-galactosidase activity (blue, X-gal, counterstain by eosin) is restricted to hippocampal neurons in CA1, DG, and neurons in the piriform cortex. The same neurons show GFPGluR-B expression when analyzed in immunohistochemical sections with an antibody against GFP. Scale bars: 500 μm.