PFA fixation-induced effects on brain tissue microstructure
| Time of fixation Structure | 30 min | 90 min | >90 min |
|---|---|---|---|
| Extracellular space | No change in VF | No change in VF No change in width | NE (dye uptake) |
| Global tissue | No visible changes | Cell blebbing | Membrane permeabilization |
| Astrocytes | NE | No changes in areas of cell bodies and main branches No changes in widths of fine processes | NE |
| Dendrites Dendritic spines | NE | “Dendritic vacuoles” No changes in spine neck length Decreased spine head area Increased spine neck width | NE |
Summary of observed changes in various tissue structures (ECS, astrocytes and dendrites) for different fixation times. VF: volume fraction; NE: not examined.