Acid sensitization of esophageal mucosal afferents: implication for symptom perception in patients across the gastroesophageal reflux disease spectrum.

Background: Sensitization of esophageal chemoreceptors, either directly by intermittent acid exposure or indirectly through esophagitis-associated inflammatory mediators, is likely to be the mechanism underlying the perception of heartburn.

Aims: To compare basal esophageal sensitivity with electrical stimulation and acid, and to compare the degree of acid-induced sensitization in controls and in patient groups across the entire spectrum of gastroesophageal reflux disease: erosive oesophagitis (EO), nonerosive reflux disease (NERD), and functional heartburn (FH).

Methods: Esophageal sensory and pain thresholds to electrical stimulation were measured before, 30, and 60 minutes after an intraesophageal infusion of saline or HCl.

Factor analysis identifies subgroups of constipation.

Aim: To determine whether distinct symptom groupings exist in a constipated population and whether such grouping might correlate with quantifiable pathophysiological measures of colonic dysfunction.

Methods: One hundred and ninety-one patients presenting to a Gastroenterology clinic with constipation and 32 constipated patients responding to a newspaper advertisement completed a 53-item, wide-ranging self-report questionnaire. One hundred of these patients had colonic transit measured scintigraphically.

Differential relaxation and contractile responses of the human upper esophageal sphincter mediated by interplay of mucosal and deep mechanoreceptor activation.

the neural mechanisms of distension-induced esophagoupper esophageal sphincter (UES) reflexes have not been explored in humans. We investigated the modulation of these reflexes by mucosal anesthesia, acid exposure, and GABA(B) receptor activation. In 55 healthy human subjects, UES responses to rapid esophageal air insufflation and slow balloon distension were examined before and after pretreatment with 15 ml of topical esophageal lidocaine, esophageal HCl infusion, and baclofen 40 mg given orally.