Figure 8.

Sympathetic efferent fibers innervating the gut exhibit complex terminal arbors. The labeled fiber in this photomicrograph (brown neurite labeled with dextran biotin) courses through and contacts myenteric ganglion cells (entering at lower right) and then turns and continues to extensively arborize in the smooth muscle wall, where it produces branches coursing both longitudinally (top to bottom of figure) and circularly (left to right of figure). Scale bar = 31 μm. Reproduced by permission of John Wiley & Sons from Walter et al.⁴⁵