Reduction of naturally-occurring cell death in the thoraco-lumbar preganglionic cell column of the chick embryo by nerve growth factor and hemicholinium-3.

A preganglionic cell column (column of Terni, CT) in the thoraco-lumbar spinal cord of avian embryos is first discernible on day 7.5-8. Between days 8 and 10 the number of visceral motoneurons in the thoraco-lumbar CT is reduced by 25-30%. Chronic administration of either nerve growth factor (NGF) or hemicholinium-3 spanning the period of naturally-occurring cell death (day 8 through day 10) increased the number of healthy neurons and decreased the number of degenerating neurons in the thoraco-lumbar CT on day 10. The number of healthy neurons in the corresponding sympathetic ganglia were also increased by NGF. Chronic administration of NGF after day 10 increased the number of healthy neurons in the thoraco-lumbar sympathetic ganglia on day 15 but had no effect on the number of motoneurons in the corresponding CT.