Gaetano Mastropaolo

Esophageal hyperalgesia in patients with ulcerative colitis: role of experimental stress

OBJECTIVES:Intestinal inflammation is associated with enteric nervous system alterations, at both inflamed and noninflamed sites. The perception of stimuli from the GI tract is enhanced during inflammatory conditions, but it is unknown whether visceral hypersensitivity is limited to the inflamed area or diffuse throughout the entire GI tract. Moreover, although stress can reactivate inflammatory processes in the gut, it is unknown if this can alter perception from the GI tract. Our aim was to determine if patients with ulcerative colitis (UC) have increased esophageal sensitivity to distention and whether this is modified by experimental stress.METHODS:Ten UC patients and 12 healthy volunteers (HVs) underwent gradual balloon distension of the esophagus to assess their visceral sensitivity. Perceptive and pain thresholds were evaluated in basal conditions and after induction of experimental stress (cold water pressure test) while blood pressure and heart rate were monitored.RESULTS:Patients with UC had perceptive thresholds to distension similar to HVs (14.8 ± 2.0 ml of air vs 14.5 ± 3.0 ml); in contrast, the volume increment needed to evoke pain was significantly lower in UC patients than in HVs (58.9% vs 149.9%, p < 0.05). Physical stress caused a similar decrease in perceptive thresholds in HVs (−29.1 ± 8.4%) and patients (−17.7 ± 9.1%), but pain thresholds were significantly decreased only in HVs (−28.3 ± 7.1% vs− 11.5 ± 12.3%).CONCLUSIONS:UC is characterized by increased esophageal sensitivity, indicating the existence of diffuse hyperalgesia during intestinal inflammatory processes. This increased sensitivity may account for the frequent upper GI symptoms these patients complain of when in clinical remission.

Psychological stress and gastric emptying in normal subjects

Gastric emptying half-time was measured in 10 healthy volunteers on two different occasions over a one-week interval, with an identical test meal. The first was the control evaluation, and at the second assessment, psychological stress was induced by the technique of dichotomous listening. Psychological and physiological parameters were assessed before and during the test period. No significant or consistent modifications of gastric-emptying time were induced by the stress procedure. Looking at individual subjects instead of mean values, gastric emptying was unchanged in 5 subjects, slower in 3, and faster in the remaining 2. These 3 groups had different mean values on two subscales of the Sixteen Personality Factor Questionnaire.