FIGURE 4. Reduction of dendrites and dendritic spines in A• ₄₂ oligomer-treated primary neurons.

A, A• ₄₂ oligomers (7 h) induced decreases in Texas-red-X-phalloidin labeled F-actin in dendrites and dendritic spines of A• oligomer-treated mature 19 DIV hippocampal neurons. The density of dendritic spines from image analysis of F-actin along dendrites confirmed significantly reduced F-actin labeling of spines in A• ₄₂ oligomer-treated neurons when compared with controls (D, ***, p • 0.001); scale bar, 25 • m. B and E, A• ₄₂ oligomers induced decreases in PSD-95 in A• oligomer-treated mature hippocampal neurons. Primary hippocampal neurons were stained with anti-PSD-95 (gray) and anti-A• (white) antibodies. Quantification of PSD-95 along dendrites revealed a significant loss (E, ***,p • 0.001); scalebar,25 • m. C, enlargement of dendrites and dendritic spines stained by X-phalloidin (gray), PSD-95 (gray), and an anti-A• polyclonal antibody, DAE (white). CTRL, control.