Intramucosal distribution of the glossopharyngeal sensory fibers of cats.

In order to determine distribution of the sensory fibers of the glossopharyngeal nerve (IX) in the pharynx of cats, wheat germ agglutinin-horseradish peroxidase was injected into the superior and inferior ganglia of IX. Results were as follows: Labeled peripheral sensory nerve fibers in the pharynx were recognized ipsilaterally. The pharyngeal branch of IX innervated the nasopharyngeal mucosa at the level of the torus tubarius. The tonsillo-lingual branch was divided into four rami. The first ramus innervated the caudal one-third of the tongue and the vallate papillae. The second ramus innervated the palatine tonsil and the caudal half of the soft palate. The third ramus supplied a part of the radix linguae, the vallecula epiglottica and the lingual aspect of the epiglottis. The fourth ramus supplied the hypopharyngeal mucosa rostral to the middle level of the aryepiglottic fold.