title: Suppression of Abdominal Motor Activity during Swallowing in Cats and Humans.
abstract: Diseases affecting pulmonary mechanics often result in changes to the coordination of swallow and breathing. We hypothesize that during times of increased intrathoracic pressure, swallow suppresses ongoing expiratory drive to ensure bolus transport through the esophagus. To this end, we sought to determine the effects of swallow on abdominal electromyographic (EMG) activity during expiratory threshold loading in anesthetized cats and in awake-healthy adult humans. Expiratory threshold loads were applied to recruit abdominal motor activity during breathing, and swallow was triggered by infusion of water into the mouth. In both anesthetized cats and humans, expiratory cycles which contained swallows had a significant reduction in abdominal EMG activity, and a greater percentage of swallows were produced during inspiration and/or respiratory phase transitions. These results suggest that: a) spinal expiratory motor pathways play an important role in the execution of swallow, and b) a more complex mechanical relationship exists between breathing and swallow than has previously been envisioned.
authors.affiliation: Department of Neurological Surgery, Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY, United States of America.
authors.forename: Teresa
authors.initials: T
authors.lastname: Pitts
authors.affiliation: Department of Physiological Sciences, University of Florida, Gainesville, FL, United States of America.
authors.forename: Albright G
authors.initials: AG
authors.lastname: Gayagoy
authors.affiliation: Department of Physiological Sciences, University of Florida, Gainesville, FL, United States of America.
authors.forename: Melanie J
authors.initials: MJ
authors.lastname: Rose
authors.affiliation: Department of Physiological Sciences, University of Florida, Gainesville, FL, United States of America.
authors.forename: Ivan
authors.initials: I
authors.lastname: Poliacek
authors.affiliation: Department of Physiological Sciences, University of Florida, Gainesville, FL, United States of America.
authors.forename: Jillian A
authors.initials: JA
authors.lastname: Condrey
authors.affiliation: Department of Physiological Sciences, University of Florida, Gainesville, FL, United States of America.
authors.forename: M Nicholas
authors.initials: MN
authors.lastname: Musselwhite
authors.affiliation: Department of Physiological Sciences, University of Florida, Gainesville, FL, United States of America.
authors.forename: Tabitha Y
authors.initials: TY
authors.lastname: Shen
authors.affiliation: Department of Physiological Sciences, University of Florida, Gainesville, FL, United States of America.
authors.forename: Paul W
authors.initials: PW
authors.lastname: Davenport
authors.affiliation: Department of Physiological Sciences, University of Florida, Gainesville, FL, United States of America.
authors.forename: Donald C
authors.initials: DC
authors.lastname: Bolser
mesh_terms: D000005:Abdomen / Q000502:physiology*; D000328:Adult; D000818:Animals; D002415:Cats; D003679:Deglutition / Q000502:physiology*; D004576:Electromyography; D004947:Esophagus / Q000502:physiology; D006801:Humans; D008297:Male; D009068:Movement / Q000502:physiology*; D015656:Respiratory Mechanics / Q000502:physiology*; D013045:Species Specificity