ENK-expressing cells project to the subiculum. A, Left, Fluorescent micrographs of hippocampo-subicular projection neurons in the CA1 area detected by EGFP immunofluorescence and retrogradely labeled after a recombinant adenovirus vector injection in the subiculum. Right, Expression of ENK and COUP-TFII in one hippocampo-subicular cell from the left. B, Colocalization of molecular markers by layer on ENK-expressing cells outside stratum pyramidale (number of counted cells). SLM, Stratum lacunosum moleculare; SR, stratum radiatum; SP, stratum pyramidale; SO, stratum oriens. Scale bars: A, left, 100 μm; right, 10 μm.