Role of tension receptors in dyspeptic patients with hypersensitivity to gastric distention  Jan Tack, Philip Caenepeel, Maura Corsetti, Jozef Janssens  Gastroenterology  Volume 127, Issue 4, Pages 1058-1066 (October 2004) DOI: 10.1053/j.gastro.2004.07.005 Copyright © 2004 American Gastroenterological Association Terms and Conditions

Figure 1 Schematic illustration of the responses of tension mechanoreceptors (in series) and elongation mechanoreceptors (in parallel) to different stimuli (distention, relaxation, and isometric contraction). Top panel represents neutral condition. In the second panel, distention is accompanied by activation of both tension and elongation mechanoreceptors, and muscular contraction status is unchanged. In the third panel, relaxation is accompanied by activation of elongation, but not tension receptors, and muscular component is lengthened. In the bottom panel, isometric contraction is accompanied by activation of tension, but not elongation receptors, and the muscular component is shortened. Gastroenterology 2004 127, 1058-1066DOI: (10.1053/j.gastro.2004.07.005) Copyright © 2004 American Gastroenterological Association Terms and Conditions

Figure 2 (A) Schematic protocol of the isovolumetric barostat study. (B) Example of a representative tracing recorded by the barostat in 1 patient with hypersensitivity to gastric distention. The upper tracing shows the intraballoon pressure recorded by the barostat; the lower tracing shows the intraballoon volume. Arrows above the tracing show increases in sensations indicated by the patient. Arrows below the tracing show perceived (black) and unperceived (white) contractions (>5 mm Hg). Note the temporal relation between sensations and contractions. Smaller pressure increases reflect respiratory variations in intraballoon pressure. Gastroenterology 2004 127, 1058-1066DOI: (10.1053/j.gastro.2004.07.005) Copyright © 2004 American Gastroenterological Association Terms and Conditions

Figure 3 (A) Corresponding mean perception scores for stepwise isobaric distentions before and after administration of placebo (left panel) and before and after administration of sumatriptan, 6 mg SC (right panel). Sumatriptan induced a significant decrease in the average perception score at the same distending pressures. (B) Pressures inducing first perception and discomfort before and after administration of placebo (left side of graph) or sumatriptan (right side). Sumatriptan induced a significant increase in pressure thresholds. (C) Corresponding intraballoon volumes at pressures inducing first perception and discomfort before and after administration of placebo (left side of graph) or sumatriptan (right side). Sumatriptan induced a significant increase in volume thresholds. Gastroenterology 2004 127, 1058-1066DOI: (10.1053/j.gastro.2004.07.005) Copyright © 2004 American Gastroenterological Association Terms and Conditions

Figure 4 (A) Influence of placebo or sumatriptan on cumulative meal-related symptom severity and on gastric half emptying time in 10 patients with functional dyspepsia and hypersensitivity to gastric distention. Sumatriptan significantly decreased meal-induced symptoms and tended to decrease gastric emptying rate. (B) Influence of placebo or sumatriptan on severity of individual meal-related symptoms. The severity of postprandial fullness, bloating, and nausea were significantly improved by pretreatment with sumatriptan (*P < 0.05 vs. placebo). Gastroenterology 2004 127, 1058-1066DOI: (10.1053/j.gastro.2004.07.005) Copyright © 2004 American Gastroenterological Association Terms and Conditions

Figure 5 (A) Influence of placebo or clonidine on cumulative meal-related symptom severity and on gastric half emptying time in 10 patients with functional dyspepsia and hypersensitivity to gastric distention. Clonidine significantly decreased meal-induced symptoms and tended to decrease gastric emptying rate. (B) Influence of placebo or clonidine on severity of individual meal-related symptoms. The severity of postprandial fullness, bloating, and nausea were significantly improved by pretreatment with clonidine (*P < 0.05 vs. placebo). Gastroenterology 2004 127, 1058-1066DOI: (10.1053/j.gastro.2004.07.005) Copyright © 2004 American Gastroenterological Association Terms and Conditions