5′‐Nucleotidase immunoreactivity of perineuronal microglia responding to rat facial nerve axotomy

Abstract
The ecto-enzyme 5′-nucleotidase was localized immunocytochemically in the axotomized rat facial nucleus. As revealed by the monoclonal antibody 5N4–2,5′-nucleotidase immunoreactivity markedly increased on perineuronal microglia during the first week following axotomy, and gradually disappeared from these cells by the end of the third post-operative week. Interestingly, parenchymal microglia were not or only weakly stained. These findings indicate that 5′-nucleotidase 5N4-2-immunoreactivity may serve as a marker for perineuronal microglia, a population of satellite glial cells that appear to be actively engaged in lesion-induced synaptic changes during regeneration.