A biomechanical response of the esophagus participates in swallowing. Am J Physiol Gastrointest Liver Physiol 2023 Feb 01;324(2):G131-G141
Date
12/14/2022Pubmed ID
36511513Pubmed Central ID
PMC9870579DOI
10.1152/ajpgi.00219.2022Scopus ID
2-s2.0-85146484570 (requires institutional sign-in at Scopus site) 1 CitationAbstract
Evidence suggests that a biomechanical process participates in esophageal function, but no such function has yet been identified. We investigated the role of a biomechanical process during swallowing in 30 decerebrate cats instrumented using electromyogram (EMG) electrodes, strain gauge force transducers, and manometry. We found that the cervical esophagus has a short-lasting circumferential tension response during the pharyngeal phase of swallowing (CTPP), and a concomitant EMG response. The CTPP magnitude was correlated with magnitudes of contraction of the geniohyoideus, laryngeal elevation force, and esophageal orad elongation force. The magnitude of the CTPP was not correlated with the peak or area under the curve of the concomitant esophageal EMG response. Restricting laryngeal elevation by physical force or transecting the hypoglossal nerves decreased or eliminated the CTPP during swallowing. Elongation of the distal cervical esophagus increased basal circumferential cervical esophageal tension as well as the CTPP. Transecting the vagus or pharyngoesophageal nerves, or administering hexosamine intravenously, had no significant effect on CTPP. We conclude that CTPP is a response to esophageal elongation during laryngeal elevation during the pharyngeal phase of swallowing, which is not caused by muscle contraction or mediated by the nervous system. The CTPP may assist in the distal movement of boluses before activation of the esophageal phase of swallowing, and may serve to prevent esophagopharyngeal reflux. We hypothesize that the CTPP is a biomechanical decrease in elasticity of the circumferential connective tissue of the cervical esophagus caused by the stress of cervical esophageal elongation.NEW & NOTEWORTHY The pharyngeal phase of swallowing includes increased circumferential tension of the cervical esophagus during the pharyngeal phase of swallowing (CTPP). The CTPP is a biomechanical response caused by elongation of the esophagus during laryngeal elevation, and is not caused by muscle contraction or mediated by the nervous system. The CTPP may assist in the distal movement of boluses before activation of the esophageal phase of swallowing, and may serve to prevent esophagopharyngeal reflux.
Author List
Lang IM, Medda BK, Kern M, Shaker RAuthors
Ivan M. Lang DVM, PhD Adjunct Professor in the Medicine department at Medical College of WisconsinBidyut K. Medda PhD Associate Professor in the Medicine department at Medical College of Wisconsin
MESH terms used to index this publication - Major topics in bold
DeglutitionGastroesophageal Reflux
Humans
Manometry
Muscle Contraction
Pharynx
Vagus Nerve
