Tolerance to gastric distension in patients with functional dyspepsia: modulation by a cholinergic and nitrergic method

Background. In patients with functional dyspepsia (FD), tolerance to gastric fundus distension is frequently compromised. We tested the contribution of contractile cholinergic or relaxing nitrergic pathways in this disorder. Methods. Thirty-nine patients (29 women, 10 men) with FD participated in this study. Gastric distension studies where carried out by inflating a fundic balloon until the maximum distension volume (MDV) tolerated by the patient. Gastric distension was first evaluated in basal control conditions before repeating the test after the injection of anticholinergic hyoscine (Buscopan 20 mg intravenous) or following the administration of nitric oxide donor nitroglycerin (Nitrolingual 1.2 mg sublingual). Results. MDVs were significantly (P < 0.01) lower in FD patients (495 +/- 27 ml) than in controls (995 +/- 59 ml). Intolerance to fundic distension was found in 77% of dyspepsia patients. Hyoscine improved the threshold for discomfort (343 +/- 21 versus 421 +/- 43 ml; P < 0.05), as well as the MDV (510 +/- 36 versus 635 +/- 44 ml; P < 0.01). This drug effect was seen in 71% (10/14) of patients. Nitroglycerin failed to modify thresholds. However, improved tolerance was seen in 15% (2/13) of the patients. Conclusion. Intolerance to fundic distension is a frequent finding in FD (77% patients). The cholinergic pathway seems to be a predominant factor involved in tolerance to distension in patients with FD. Fundus-relaxing drugs should be considered for the treatment of dyspepsia.