Studies in health have shown that tension-sensitive mechanoreceptors mediate sensitivity to gastric distention.
A role for these mechanoreceptors in perception or symptoms in hypersensitive functional dyspepsia (FD) has not been established.
Tension-sensitive mechanoreceptors are activated during phasic contractions and inactivated during gastric relaxation.
Dr Jan Tack and colleagues from Leuven, Belgium undertook a study to investigate whether hypersensitive FD patients perceive spontaneous changes in fundic wall tension.
In addition, they assessed whether fundus-relaxing drugs decrease sensitivity to gastric distention and meal-related symptoms.
The research group selected 50 patients in total, after a barostat study established gastric hypersensitivity.
The researchers inflated an intragastric balloon to a fixed volume below perception thereshold in 12 patients.
|Findings are compatible with involvement of tension mechanoreceptors in symptom generation in hypersensitive FD|
The researchers then asked the participants to indicate changes in perception on a keypad for analysis of the relationship between perception and contractions.
In 20 patients, the research team studied the influence of the fundus-relaxing drug sumatriptan on sensitivity to gastric distention.
In, respectively, 10 and 8 patients, the researchers studied the influence of the fundus-relaxing drugs sumatriptan and clonidine on meal-related symptoms.
The researchers found that the majority of patients had a statistically significant association between perception and phasic isovolumetric contractions.
In addition, they found that pretreatment with sumatriptan increased both pressures and volumes needed to induce first perception and discomfort.
Pretreatment with sumatriptan and clonidine both significantly decreased meal-induced symptoms.
Dr Tack concluded, "Patients with hypersensitivity to gastric distention perceive isovolumetric phasic contractions of the proximal stomach."
"Fundus-relaxing drugs decrease sensitivity to gastric distention and decrease meal-induced symptoms in these patients."
"The findings are compatible with involvement of tension mechanoreceptors in symptom generation in hypersensitive FD."