耳管におけるアドレナリン作働神経分布に関する組織化学的研究

Abstract

There is much clinical evidence of a close relationship between the eustachian tube and the autonomic nervous system, especially in otitis media with effusion. However, the anatomical distribution of the autonomic nerves is not known.Superficial and topographical adrenergic innervation of the tube was demonstrated by the glyoxylic acid method. The nerve fibers were most abundant in the pharyngeal area, sparser in the middle, and even fewer in the tympanic part. The fibers were arranged in an essentially longitudinal manner in all specimens. In the pharyngeal area, the adrenergic plexus formed a loose network of varicose fibers.The cellular location of adrenergic nerves in the tube was then observed in freeze-dried sections by the Falck-Hillarp fluorescence method. Abundant adrenergic nerve fibers forming a network were observed around blood vessels, especially arteries of all the tubal regions. In the lamina propria of the tube, some varicose adrenergic nerve fibers ran separate from blood vessels, and they were abundant in the pharyngeal area. Adrenergic fibers were also seen around the tubal glands.The superior cervical ganglion was transsected to investigate the adrenergic nerve pathways and their origin.No adrenergic nerve was seen in the perivascular region or around the glands after transsection of this ganglion.These studies show that the adrenergic nerve arises from the superior cervical ganglion and reaches the eustachian tube through the tympanic plexus and along the vessels supplying the tube from the external carotid artery.The adrenergic nerve seems to affect the patency of the eustachian tube by controlling vasoconstriction. It is also speculated that patency of the tube is controlled by the adrenergic nervous system through the mucociliary system and the glands in the pharyngeal area.