Fig. 3.

Cutting both nerve roots greatly enhances the growth of the longitudinal projections of the AP cell. The difference in relative length was calculated as the difference in relative length (as defined in Fig. 2A) between the longitudinal projections of the experimental AP neuron (the lateral projections of which were cut) and those of the intact contralateral homolog in the same ganglion. By 14–15 hr after root cutting, the relative lengths of both the anterior and posterior longitudinal projections of the experimental cells were significantly longer than controls. The posterior longitudinal projection grew significantly more than the anterior one at both 14–15 hr and 21 hr after the surgery.