Distribution of tdTomato fluorescence in ileal enteric neurons. A: Bright fluorescence was seen in vagal preganglionic fibers projecting to the myenteric plexus as well as numerous, but not all, enteric neurons (whole mount, 10×, 14 optical plans, 2.8-μm step, 4 tiles). Of note, projections from the enteric neurons were seen ramifying into the adjacent smooth muscle layers. B: Likewise, submucosal neurons and their projections and clearly labeled. Scale bar = 100 μm in A (also applies to B).