Figure 4. Immunocytochemical analyses of NAPE-PLD, FAAH, NAAA, CB₁ and PPAR alpha in dentate gyrus 24hpl.

Left column: DG in overview after DAB staining. Middle column; Triple staining of eCB system related proteins with NeuN and IB₄. Right column; Triple staining of OHSC with eCB system related proteins in combination with NeuN and GFAP. The granular cell layer of the DG and interneurons in the hilus region showed a strong immunoreaction for NAPE-PLD. No overlap was observed with GFAP or IB₄. The granular cell layer of the DG and especially interneurons in the hilus region were strongly immunoreactive for FAAH. No overlap was observed with GFAP or IB₄. Please note the similarity of staining pattern of NAPE-PLD and FAAH immunoreactions. NAAA was found in perikarya and nuclei of neurons. In addition to granular cell layer of the DG and hilar neurons CA3 region was strongly labeled. Astrocytes and microglia seem free of NAAA. The entire molecular layer of the dentate gyrus showed a positive CB₁ immunoreaction. CB₁ was present in Microglia and to a lesser extent in astrocytes. PPAR alpha was observed in perikarya and nuclei of neurons. Microglia and Astrocytes showed a positive immunoreaction for PPAR alpha (n = 3, bars: left column = 100 µm, middle and right columns = 50 µm).