title: Multimodal pain stimulations in patients with grade B oesophagitis.
abstract: OBJECTIVE
  To obtain a better understanding of nociceptive processing in patients with oesophagitis.
  
  
  METHODS
  Eleven patients with grade B oesophagitis were compared with an age and sex matched group of 16 healthy subjects. A probe was positioned in the lower part of the oesophagus. After preconditioning of the tissue, painful mechanical stimuli were applied as distensions with a bag using an impedance planimetric method. Distensions were done before and after pharmacological impairment of distension induced smooth muscle contractions. Thermal stimulation was performed by recirculating water at 1 and 60 degrees C in the bag. The area under the temperature curve (AUC) represented caloric load. The referred pain area (being a proxy for the central pain mechanisms) to the mechanical stimuli was drawn at maximum pain intensities.
  
  
  RESULTS
  Patients were hyposensitive to mechanical stimuli, as assessed by the distending volume (F=8.1, p=0.005). After relaxation of smooth muscle with butylscopolamine, the difference between the two groups was more evident (F=27.4, p<0.001). AUC for cold stimulation was 1048.6 (242.7) degrees Cxs in controls and 889.8 (202.6) degrees Cxs in patients (p=0.5). For heat stimuli, AUC values were 323.3 (104.1) and 81.3 (32.3) degrees Cxs in controls and patients, respectively (p=0.04). The referred pain area to the mechanical stimulations was larger and more widespread in patients (49.3 (6.2) cm2 compared with controls 23.9 (7) cm2; p=0.02).
  
  
  CONCLUSIONS
  The data indicate that peripheral sensitisation of heat sensitive receptors and pathways combined with facilitation of central pain mechanisms may explain the symptoms in patients with oesophagitis.
authors.affiliation: Centre for Visceral Biomechanics and Pain, Department of Medical Gastroenterology, Aalborg Hospital, DK-9100, and Centre for Sensory-Motor Interaction (SMI), Department of Health Science and Technology, Aalborg University, Denmark. drewes@smi.auc.dk
authors.forename: A M
authors.initials: AM
authors.lastname: Drewes
authors.forename: H
authors.initials: H
authors.lastname: Reddy
authors.forename: J
authors.initials: J
authors.lastname: Pedersen
authors.forename: P
authors.initials: P
authors.lastname: Funch-Jensen
authors.forename: H
authors.initials: H
authors.lastname: Gregersen
authors.forename: L
authors.initials: L
authors.lastname: Arendt-Nielsen
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D016022:Case-Control Studies; D003080:Cold Temperature / Q000009:adverse effects; D004558:Electric Stimulation; D004941:Esophagitis / Q000503:physiopathology*; D004947:Esophagus / Q000503:physiopathology*; D005260:Female; D006358:Hot Temperature / Q000009:adverse effects; D006801:Humans; D007858:Learning; D008297:Male; D008875:Middle Aged; D009619:Nociceptors / Q000502:physiology*; D017288:Pain Threshold; D013314:Stress, Mechanical