Fig. 6.

An RPeD1 soma induced the positive turning of a target cell growth cone, which was inhibited in the presence of the D₂ antagonist. RPeD1 somata were placed 75–100 μm away (and at an angle) to advancing target cell growth cones (A, Bi, 0 min). The target growth cones began to turn toward the RPeD1 somata (Aii, 90 min;Bii, 60 min) and continued to advance in the direction of RPeD1 (A, Biii, 120 min).C, The D₂ antagonist sulpiride (10⁻⁵m) was added to the bathing medium before the manipulation of the RPeD1 soma (i, 0 min). In the presence of the dopamine receptor antagonist, the growth cone did not turn (ii, 60 min) and continued to advance on its original path (iii, 90 min). Scale bars:A–C, 50 μm.