Overcoming the failure of electronmicroscopy to preserve the brain's extracellular space

Abstract The space between neurones and glial cells in the brain adds up to about one-fifth of brain volume, but this nearly all disappears at fixation, and electronmicrographs are normally distorted, showing a space of less than 5%. A simple alteration of the fixing process prevents this artefact occurring, and electronmicroscopy then shows an interesting distribution of extracellular space.