Faculty Collaboration Database

Mechanisms of reflexes induced by esophageal distension. Am J Physiol Gastrointest Liver Physiol 2001 Nov;281(5):G1246-63

Date

10/23/2001

Pubmed ID

11668034

DOI

10.1152/ajpgi.2001.281.5.G1246

Scopus ID

2-s2.0-0035204455 (requires institutional sign-in at Scopus site)   121 Citations

Abstract

We investigated the mechanisms of esophageal distension-induced reflexes in decerebrate cats. Slow air esophageal distension activated esophago-upper esophageal sphincter (UES) contractile reflex (EUCR) and secondary peristalsis (2P). Rapid air distension activated esophago-UES relaxation reflex (EURR), esophago-glottal closure reflex (EGCR), esophago-hyoid distraction reflex (EHDR), and esophago-esophagus contraction reflex (EECR). Longitudinal esophageal stretch did not activate these reflexes. Magnitude and timing of EUCR were related to 2P but not injected air volume. Cervical esophagus transection did not affect the threshold of any reflex. Bolus diversion prevented swallow-related esophageal peristalsis. Lidocaine or capsaicin esophageal perfusion, esophageal mucosal layer removal, or intravenous baclofen blocked or inhibited EURR, EGCR, EHDR, and EECR but not EUCR or 2P. Thoracic vagotomy blocked all reflexes. These six reflexes can be activated by esophageal distension, and they occur in two sets depending on inflation rate rather than volume. EUCR was independent of 2P, but 2P activated EUCR; therefore, EUCR may help prevent reflux during peristalsis. All esophageal peristalsis may be secondary to esophageal stimulation in the cat. EURR, EHDR, EGCR, and EECR may contribute to belching and are probably mediated by capsaicin-sensitive, rapidly adapting mucosal mechanoreceptors. GABA-B receptors also inhibit these reflexes. EUCR and 2P are probably mediated by slowly adapting muscular mechanoreceptors. All six reflexes are mediated by vagal afferent fibers.

Author List

Lang IM, Medda BK, Shaker R

Authors

Ivan M. Lang DVM, PhD Adjunct Professor in the Medicine department at Medical College of Wisconsin
Bidyut K. Medda PhD Associate Professor in the Medicine department at Medical College of Wisconsin
Reza Shaker MD Assoc Provost, Sr Assoc Dean, Ctr Dir, Chief, Prof in the Medicine department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Afferent Pathways
Animals
Baclofen
Cats
Decerebrate State
Electromyography
Esophagogastric Junction
Esophagus
Female
Insufflation
Male
Mucous Membrane
Muscle Contraction
Muscle Relaxants, Central
Peristalsis
Pharyngeal Muscles
Reflex
Stress, Mechanical
Time Factors