Fig. 1. Wholemount small bowel myenteric plexus staining for Gdnf^+/–, Gdnf^+/–/Nrtn^–/–, Nrtn^–/– and wild-type mice. (A,B) Cuprolinic Blue staining highlights clustered neuronal cell bodies (red arrows) without showing neuronal processes. Gdnf^+/– mice (B) have fewer neurons, but normal neuronal cell size. (C-F) Acetylcholinesterase stains both neuronal cell bodies and fibers. Gdnf^+/– mice (D) have a normal density of acetylcholinesterase-stained fibers compared with wild-type (C). Nrtn^–/– (E) and Gdnf^+/–/Nrtn^–/– (F) mice have an obvious loss of small acetylcholinesterase-stained neuronal fibers. Black arrowheads identify small fibers and fiber bundles in Gdnf^+/– and Gdnf^+/–Nrtn^–/– mice (D,F). Scale bar: 100 µm.