Fig. 1

Postsynaptic reduction of GIRK2 in CA1 pyramidal cells of APP/PS1 mice. Electron micrographs showing postsynaptic immunoparticles for GIRK2 in the stratum radiatum of the hippocampal CA1 field at 12 months of age, as detected using the SDS-FRL technique in wild type and APP/PS1 mice. A–C In wild type, GIRK2 immunoparticles were detected forming clusters (blue circles) or scattered (blue arrows) and associated with the P-face in dendritic spines (s) and oblique dendrites (oDen) of CA1 pyramidal cells. D–F In APP/PS1, very low frequency of clusters or scattered (blue arrows) GIRK2 immunoparticles were observed in dendritic spines (s) and oblique dendrites (oDen) of CA1 pyramidal cells. The E-face is free of any immunolabelling. G Quantitative analysis showing that the density of surface GIRK2 immunoparticles was significantly reduced in the APP/PS1 mice compared to age-matched wild type controls in the two subcellular compartments analysed (Mann–Whitney test, ****p < 0.0001). Error bars indicate SEM. Scale bars: A–F, 0.2 μm