Delayed dendritic development of catecholaminergic neurons in the ventrolateral medulla of children who died of sudden infant death syndrome.

Catecholaminergic neurons were characterized by reaction with antiserum to tyrosine hydroxylase, by shape and location and by dendritic ramifications. In this population of cells in the ventrolateral medulla (VLM), the dendritic spines of fusiform and triangular neurons increased with gestational age and rapidly diminished after birth. However, in SIDS, the spines persisted notably in neurons in the VLM but also in the reticular formation and vagal nuclei. These findings suggest a delay in neuronal maturation and may be related to developmental disorders of respiratory, circulatory or sleep-wake regulation.