title: Histological identification of nasopharyngeal mechanoreceptors.
abstract: The auditory tube plays a fundamental role in regulating middle ear pressure. A "system" sensitive to a pressure gradient between the middle ear and the ambient environment is necessary. The presence of mechanoreceptors in the middle ear and the tympanic membrane has been studied, but the presence of these receptors in the nasopharyngeal region remains unclear. The aim of this study is to confirm the presence of pressure sensitive corpuscles in the nasopharynx. An experimental study was conducted on five fresh and unembalded human cadavers. The pharyngeal ostium of the auditory tube and its periphery was removed in one piece by video-assisted endonasal endoscopy. Samples were fixed in formaldehyde solution, embedded in paraffin, and cut. Slides were analyzed by HES (Hematoxyline Eosine Safran) coloration, by S100 protein and neurofilament protein immunostaining. Encapsulated nerve endings were researched and identified by slides analysis. Eight samples were included in our study. On seven samples, Ruffini corpuscles were identified in the mucosa of the posterior area of the pharyngeal ostium, with a higher concentration in the pharyngeal recess and in the posterior nasopharyngeal wall. Our study identified nasopharyngeal mechanoreceptors that could detect the nasopharyngeal pressure and, by extension, the atmospheric pressure. These findings support the theory of the neuronal reflex arc of isobaric system of the middle ear, based on the existence of a "system" sensitive to a pressure gradient between the middle ear and the ambient environment. Understanding of this system has been helpful in the diagnosis and management of middle ear diseases.
authors.affiliation: APHM, Hôpital de la Conception, Service d'oto-rhino-laryngologie et de chirurgie cervico-faciale, 147 Boulevard Baille, 13005, Marseille, France.
authors.forename: Florent
authors.initials: F
authors.lastname: Salburgo
authors.affiliation: Aix Marseille Université, INSERM, U1070, 13288, Marseille, France.|APHM, Hôpital Nord, Laboratoire d'anatomie pathologique, 13915, Marseille, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Garcia
authors.affiliation: APHM, Hôpital de la Conception, Service d'oto-rhino-laryngologie et de chirurgie cervico-faciale, 147 Boulevard Baille, 13005, Marseille, France.|Aix Marseille Université, CNRS, LPL, UMR 7309, 13344, Marseille, France.
authors.forename: Aude
authors.initials: A
authors.lastname: Lagier
authors.affiliation: APHM, Hôpital de la Conception, Service d'oto-rhino-laryngologie et de chirurgie cervico-faciale, 147 Boulevard Baille, 13005, Marseille, France.
authors.forename: Dominique
authors.initials: D
authors.lastname: Estève
authors.affiliation: APHM, Hôpital de la Conception, Service d'oto-rhino-laryngologie et de chirurgie cervico-faciale, 147 Boulevard Baille, 13005, Marseille, France.|Aix Marseille Université, IFSSTAR, LBA, UMR-T 24, 13344, Marseille, France.
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Lavieille
authors.affiliation: APHM, Hôpital de la Conception, Service d'oto-rhino-laryngologie et de chirurgie cervico-faciale, 147 Boulevard Baille, 13005, Marseille, France. marion.montava@ap-hm.fr.|Aix Marseille Université, IFSSTAR, LBA, UMR-T 24, 13344, Marseille, France. marion.montava@ap-hm.fr.
authors.forename: Marion
authors.initials: M
authors.lastname: Montava
mesh_terms: D000369:Aged, 80 and over; D002102:Cadaver; D005064:Eustachian Tube / Q000166:cytology; D005260:Female; D006801:Humans; D008297:Male; D008465:Mechanoreceptors / Q000166:cytology*; D008853:Microscopy; D009092:Mucous Membrane / Q000166:cytology; D009305:Nasopharynx / Q000166:cytology*
keywords: Auditory tube; Eustachian tube; Mechanoreceptors; Middle ear pressure; Nasopharynx; Sensory receptors