Fig. 4.

Chronic high-resolution imaging of dendritic spines with in vivo 2PE microscopy. High-resolution images of dendritic spines acquired with in vivo 2PE microscopy before and after stroke. The day of imaging is shown in the lower right-hand corner. Shown is an apical dendritic segment from a layer 5 pyramidal neuron in peri-infarct cortex before (green) and after (red) unilateral permanent middle cerebral artery occlusion (MCAO) in mice. All images are maximum intensity projections (4–7 slices, 1.5 μm apart). A few examples of always present spines (yellow arrowheads), gained spines (green arrowheads), and lost spines (red arrowheads) are shown. Blue asterisks at +4 d post MCAO denote transient dendritic swelling after stroke. See Mostany et al. [18] for details