Assessment of neural inhibition of the lower esophageal sphincter in cats with esophagitis.
BACKGROUND
The aim of this study was to investigate the inhibitory innervation of the lower esophageal sphincter in the presence of esophagitis.


METHODS
Esophagitis was produced in five anesthetized cats with intraesophageal perfusion of HCl. Sphincter pressure responses were assessed with a sleeve catheter after administration of bethanechol, cholecystokinin octapeptide, and McNeil-A343 and with intraesophageal balloon distension.


RESULTS
In the presence of esophagitis (1) resting lower esophageal sphincter pressure decreased; (2) the excitatory response to bethanechol was maintained; (3) there was a reduction in the excitatory response to McNeil-A343 and cholecystokinin at the highest dosages; (4) there was an increase in the potency of cholecystokinin and McNeil-A343 to produce an inhibitory response; (5) the inhibitory response to intraesophageal balloon distension was maintained; and (6) increased inhibitory responses took longer to normalize than the reduced excitatory responses.


CONCLUSIONS
Esophagitis decreases cholinergic excitation, but neural inhibition to the LES remains intact. These findings suggest that blocking intact inhibition may be a new therapeutic approach for esophagitis caused by gastroesophageal reflux.
Salapatek
A M
AM
Department of Medicine, University of Toronto, Playfair Neurosciences, Ontario, Canada.
Diamant
N E
NE
D008455:(4-(m-Chlorophenylcarbamoyloxy)-2-butynyl)trimethylammonium Chloride / Q000494:pharmacology; D000208:Acute Disease; D000818:Animals; D018723:Bethanechol; D001626:Bethanechol Compounds / Q000494:pharmacology; D002415:Cats; D004941:Esophagitis / Q000503:physiopathology*; D004943:Esophagogastric Junction / Q000187:drug effects / Q000294:innervation* / Q000502:physiology; D004947:Esophagus / Q000473:pathology; D005260:Female; D008297:Male; D009433:Neural Inhibition; D012844:Sincalide / Q000494:pharmacology
D001626:Bethanechol Compounds; D018723:Bethanechol; D008455:(4-(m-Chlorophenylcarbamoyloxy)-2-butynyl)trimethylammonium Chloride; D012844:Sincalide