Fig. 7.

Innervation after chorda-lingual nerve transection. A–C: Profiles of taste buds from a mouse 10 days after unilateral chorda-lingual nerve transection. Fibers positive for neurofilament and PGP 9.5 are in green, cytokeratin 8-positive cells are in magenta. Taste buds on the contralateral, intact side of the tongue were richly innervated with neurofilament 150-positive fibers (A). On the transected side of the tongue, no fibers were observed in empty papilla (B) or papilla with remnant fungiform taste buds (C). The arrow indicates hypoglossal fibers innervating underlying muscle tissue. D–F: Profiles of taste buds 20 days after chorda-lingual nerve transection. These include an intact taste bud contralateral to nerve transection (D), neural fibers in an empty fungiform papilla (E), and fibers approaching a small, remnant fungiform taste bud (F). To confirm the lack of chorda-lingual fibers 10 days after nerve transection, G–I show PGP 9.5 immuno-like staining. Taste buds on the intact side of the tongue show prolific staining for PGP 9.5 (G), while the cut side lacks PGP 9.5 staining in empty fungiform papilla (H) and in the presence of a fungiform taste bud (I). Scale bars = 20 µm.