In vitro and in situ formation of neuron-glia junctions

The formation of neuron-glia junctions during neurogenesis has been considered as an error of the neuronal specificity mechanism or as a consequence of the artificial conditions when observed in central nervous system tissue culture. We report the demonstration of the regular existence of synaptic-like junctions in tissue cultures prepared from different regions of chick central nervous system as well as the occurrence of such intercellular contacts in the cerebellum of adult and normal frogs. The formation of neuron-glia junctions in tissue culture during normal neurogenesis and their presence in adult frogs seem to indicate that those types of neuron-glia relationships are not a simple biologic error. Rather, we propose that they may represent a primitive, but normal neuron-glia interaction.