NOS-I and sGCβ in dendritic spines. The lipophilic dye DiA (green), which stains the entire plasma membrane of scattered CA1 pyramidal neurons, allows appreciation of the relationship of antigen to dendrites and dendritic spines. A (top panel), Low-magnification overview of the relationship of immunostaining for NOS-I (red) and sGCβ (blue) with apical dendrites of pyramidal neurons stained with DiA. B,C, High-magnification views of boxed areas. Arrowheads point to dendritic spines immunopositive for NOS-I, associated with puncta immunopositive for sGCβ. Scale bars: A, 10 μm; B, 2.5 μm; C, 2 μm.