Development of neuron-specific enolase immunoreactivity in avian nervous tissue in vivo and in vitro.

Neuron-specific enolase (NSE) is a glycolytic isoenzyme that is primarily located in neurons and neuroendocrine cells. The development of NSE immunoreactivity in th avian nervous system at the level of the hind limb has been examined using immunocytochemical methods. NSE immunoreactivity is first detected in ventral horn motor neurons and dorsal root ganglion neurons at embryonic day 9-10. This is at least 2-3 days after some neurons in both these populations are capable of electrical activity. The glycogen body, a non-neuronal structure, also exhibits NSE (+) staining, but the onset of this immunoreactivity is earlier, at 8 days of embryonic development. NSE immunoreactivity was absent from the cell bodies of paravertebral sympathetic ganglia throughout development, but was present in cellular processes and terminals in the adult ganglia. NSE immunoreactivity also develops in tissue cultures containing cells of neural tube and neural crest origin.