title: The effect of eating on lower esophageal sphincter electrical activity.
abstract: Electrical activity of the lower esophageal sphincter (LES) has been recorded mainly in vitro and in anesthetized animals. Swallowing produces relaxation of the LES, followed by its contraction. These changes should be associated with changes in LES electrical activity. To determine whether changes in LES electrical activity can be used to recognize the beginning of a meal, four dogs were implanted with two electrodes in the longitudinal axis of the LES. The electrodes were connected to an implantable device for recording of electrical activity. After recovery, dogs underwent two experiments: 1) combined recordings of LES electrical activity and esophageal manometry to test the effect of dry swallows, water, and solid food swallows on LES electrical activity and 2) telemetric recording of LES electrical activity during a standard meal. All amplitudes were in mV, means+/-SD, ANOVA, P<0.05. In experiment 1, an increase in the amplitude of LES electrical activity was associated with the substance being swallowed, i.e., at rest: 0.31+/-0.06; dry swallows: 0.6+/-.0.1; water: 0.67+/-0.12; solid food: 1.06+/-0.17, P<0.001. In experiment 2, there was a pronounced and characteristic increase in amplitude of LES electrical activity during feeding, 0.26+/-0.1; during fasting, 0.99+/-0.23; while eating, 0.31+/-0.1 postprandial, P<0.001. In conclusion, the beginning and duration of a meal are identified by distinct, easily recognizable changes in the amplitude of LES electrical activity. These changes depend on the type of the substance being swallowed and are most prominent with solid food. Changes in LES electrical activity can potentially be used for automatic eating detection.
authors.affiliation: Gastrointestinal Motility Program, Department of Minimally Invasive Surgery, Cedars Sinai Medical Center, 8730 Alden Dr., Thalians Bldg., 2nd Floor East, Los Angeles, CA 90048, USA.
authors.forename: Claudia P
authors.initials: CP
authors.lastname: Sanmiguel
authors.forename: Yuichiro
authors.initials: Y
authors.lastname: Ito
authors.forename: Masanobu
authors.initials: M
authors.lastname: Hagiike
authors.forename: Jeffrey L
authors.initials: JL
authors.lastname: Conklin
authors.forename: David
authors.initials: D
authors.lastname: Lalezari
authors.forename: Edy E
authors.initials: EE
authors.lastname: Soffer
mesh_terms: D000818:Animals; D003679:Deglutition / Q000502:physiology; D004285:Dogs; D004435:Eating / Q000502:physiology*; D004594:Electrophysiology; D049630:Esophageal Sphincter, Lower / Q000502:physiology*; D005260:Female