The origin of autonomic nerves of the Eustachian tube as studied by the horseradish peroxidase tracer method.

Autonomic innervation of the Eustachian tube mucosa was investigated by the horseradish peroxidase retrograde tracing method. The Eustachian tube mucosa was found to be sympathetically innervated by fibres originating in the ipsilateral superior and middle cervical ganglia, but not by those originating in the stellate ganglion. The Eustachian tube mucosa was also innervated by fibres originating in the pterygopalatine ganglion, but not by those originating in the otic ganglion. The innervation from the pterygopalatine ganglion was considered to be parasympathetic.