Localization of GHSR1a in cultured hippocampal slices. A-C. Binding of octanoylated form of FITC-conjugated ghrelin (F302, 1 μM) in the CA3 and CA2 of rat hippocampal slices (A), which extended to CA1 (B). The lack of binding with non-octanoylated form of FITC-conjugated ghrelin (F203, 1 μM) (C). D and E. Octanoylated ghrelin-binding (F302) (D) and non-octanoylated ghrelin-binding (F203) (E) in CA1 neurons. F. GHSR1a immunoreactivity. G-J. eGFP signals from GHSR1a-expressing cells in the RgS transgenic line of mouse hippocampal slices (G). The eGFP signals in the CA1 region with higher magnifications (H and I). Individual CA1 pyramidal cells expressing eGFPs (J). Images in A-F were obtained in fixed slices, and images in G-J were obtained in live slices. Calibrations: 500 μm in A, B, C and G; 200 μm in H; 100 μm in I; 10 μm in D, E and J; 5 μm in F.