FIGURE 6.

Early and later stage of neuritogenesis. A, images of a Neuro-2a cell at 5-min intervals during the early stage of neuritogenesis. The arrowhead indicates the neurite that retracts to the cell body after 10 min. B, images of Neuro-2a cells at the later stage of neuritogenesis, when neurites become axons. The numeric value indicates the number of the neurite, and the arrow indicates the neurite that is an axon. After 20 min of neuritogenesis, neurite 1, which was an axon, becomes a neurite, whereas neurite 2 becomes an axon. Scale bar, 10 μm.