INFLUENCE OF MIGRATING MOTOR COMPLEX ON ESOPHAGEAL MOTILITY

In most fasting mammals motility of the foregut and small intestine undergoes regular cycles of activity. The phenomenon has been called the interdigestive migrating myoelectric complex or the migrating motor complex. As shown in published literature, feeding interrupts the cycle and changes the interdigestive fasted pattern into a pattern of irregular spiking activity, which has been called the fed pattern. The mapping of the migrating motor complex throughout the upper gut demonstrated major regional variations. The incidence of migrating motor complex at multiple sites from distal esophagus to cecum approximated a normal distribution. In the course of esophageal manometric studies the influence of migrating motor complex on lower esophageal sphincter was observed. This observation raised the question whether future pharmacomanometric studies should be performed with volunteers in the fasting state as done until now. According to published literature, lower esophageal sphincter pressure is significantly higher during migrating motor complex phase III than phase I; differences are approximately twofold. Fifty percent of migrating motor complexes involve the esophagus. The migrating motor complex in some individuals interferes significantly with esophageal pharmacomanometry provided the volunteers are fasted. On the other hand postprandial lower esophageal sphincter pressure was rather constant at a level comparable with that measured in migrating motor complex phase I. The consequences of this phenomenon for the study design in pharmacomanometry are discussed.