Effect of 5-hydroxytryptamine receptor 4 agonist mosapride on human gastric accommodation.

BACKGROUND: Impaired gastric accommodation is one of the major features of functional dyspepsia. Mosapride citrate is a 5-hydroxytryptamine receptor 4 (5-HT4) agonist, which is shown to improve upper abdominal symptoms. However, effect of mosapride on gastric accommodation was not clear. We tested the hypothesis that mosapride enhances the gastric accommodation in normal individuals. METHODS: Fourteen male healthy volunteers completed this study. Single administration of mosapride or placebo was performed randomly with more than 1-week interval. Subjects swallowed a triple-lumen polyvinyl tube with a polyethylene bag. The bag was positioned in the proximal stomach and the minimal distending pressure (MDP) was determined. The ramp distension starting from the MDP was then performed and subjects were instructed to score their perception using ordinate scales. Next the intra-bag pressure was set at MDP + 2 mmHg and a liquid meal was administered 30 min later, and the intra-bag volume was recorded for 60 min. We compared the MDP, perception scores, and the intra-bag volume changes by administering placebo and mosapride. KEY RESULTS: Minimal distending pressure was not significantly different in subjects receiving mosapride or placebo. Treatment with mosapride had no effect on intra-bag pressures or volumes inducing first sensation or discomfort. Gastric accommodation, expressed as the difference between pre- and postmeal intra-bag volumes, and the percent change of the intra-bag volumes by the meal was significantly enhanced by mosapride compared with placebo. CONCLUSIONS & INFERENCES: This is the first study clearly demonstrating that single administration of 5-HT4 agonist can enhance gastric accommodation in humans. (Umin.ac.jp, number UMIN000014063).

Bilevel nasal positive airway pressure and ballooning of the stomach.

We describe a case of severe gastric insufflation in a patient with amyotrophic lateral sclerosis who was receiving bilevel nasal positive airway pressure (BNPAP) ventilation (BiPAP; Respironics; Murrysville, PA). The injection of inspiratory flow into the esophagus, aerophagia, and air trapping below the gastroesophageal junction after a meal are probably the major causes. We suggest that BNPAP ventilation can be a cause of serious gastric insufflation in a patient who lies supine, especially after a meal, and attention should be paid to avoiding this complication by having the patient sit up for about half an hour after a meal.

[Variant angina due to deficiency of intracellular magnesium by anorexia nervosa].

A 51-year-old man who had a past history of gastric resection for medically uncontrollable gastric ulcer has loss of appetite that recurs periodically. And he has frequently presented spontaneous angina early in the morning since 1984. He was diagnosed as having variant angina by the documentation of typical ST elevation during anginal attack and also by showing coronary artery spasm (#2 and #12) during hyperventilation on coronary arteriography. A large quantity of calcium blocking agents and nitrates could not improve his symptoms. Lack of intracellular magnesium by loss of appetite was suspected from a daily excretion of urine magnesium (5.3 mEq) and magnesium tolerance test (56.7%). To confirm the effect of magnesium administration, the second coronary arteriography was performed. After magnesium sulphate (80 mEq, hourly) was injected, coronary artery spasm could not be induced by ergonovine. And orally magnesium oxide, calcium blocking agents and nitrates were started. Anginal attack disappeared with increasing urine magnesium.