The role of interdigestive gallbladder emptying in
gallstone formation is unknown. In fasting healthy subjects, gallbladder emptying is associated with
antral phase III of the migrating motor complex (MMC) and high plasma
motilin. Therefore, gallbladder volumes and
motilin levels were measured during 13 MMC cycles in 10
cholesterol gallstone patients and compared with 20 MMC cycles in 10 healthy subjects. MMC cycle length was longer in
gallstone patients than in healthy subjects (158.2 +/- 17.0 vs 105.5 +/- 10.4 min, respectively; P < 0.05), due to longer phase I (39.8 +/- 5.7 vs 17.2 +/- 3.7 min, respectively; P < 0.05). In contrast to healthy subjects,
gallstone patients had no significant fluctuations of gallbladder volume during the MMC cycle, and
motilin concentrations were not different in MMC cycles with phase III originating in antrum or duodenum. During MMC cycles with phase III originating in the duodenum,
motilin levels were twice as high in
gallstone patients as in healthy subjects (P < 0.002). In conclusion,
cholesterol gallstone patients have an abnormal MMC and
motilin release pattern. Their interdigestive gallbladder emptying is reduced and dissociated from the MMC. These disturbances may contribute to
gallstone formation.