Fig. 6

Wnt3a ligand promotes autophagic vesicle formation in the CA1 region of the rat hippocampus. Hippocampal slices were oxygenated in ACSF and treated for 4 h with Wnt3a ligand, lithium and metformin. Ultrastructural analyses were performed to visualize autophagic vesicles (AVs) (see graph). In the control slices, normal synapses containing synaptic vesicles are shown with the postsynaptic density (first column; see white arrow). The number of vesicles per image was determined by counting two vesicle types. Early vesicles (AV1) were defined by a large double membrane containing amorphous material (Wnt3a ligand treatment; second column, zoomed-in red square), and late autophagic vesicles (AV2) were characterized by a single-membrane vesicle containing electron-dense intraluminal material (e.g., zoomed-in Wnt3a ligand treatment; blue square). The representative photograph at 20500× magnification shows regions of interest. The data are expressed as the mean ± S.E.M. of 20–25 micrographs of three independent experiments, *p < 0.05, ***p < 0.0001; the scale bar represents 1 μm