The development and ultrastructure of previously dissociated embryonic chick corpus striatum cultured on feeder layers of liver cells.

Embryonic chick corpus striatum neurons were dissociated and maintained on liver feeder layers in culture. Although some large dark-cored vesicles were present in many nerve processes and presynaptic boutons they were substantially less numerous than chick spinal cord neurons grown under identical conditions. Paraformaldehyde-induced fluorescence, although observed in a few culture batches in aggregates of corpus striatum neurons, was otherwise absent and no decisive evidence was obtained to suggest that fluorescent corpus striatum neurons were commonly developed on liver feeder layers in culture. Microtubules filled most cell bodies and nerve processes, and extended well into synaptic boutons often approaching the active zones. They were much more abundant in cultures of corpus striatum than in comparable spinal cord preparations and formed the principal organelle of many nerve fibres. These differences between chick spinal cord and corpus striatum neurons are both interesting and difficult to interpret. It is possible that fewer appropriate cholinergic neurons are available for transformation into adrenergic neurons within the corpus striatum, and that excessive numbers of dark-cored vesicles indicate only a greatly increased rate of acetylcholine production and storage.