Diurnal changes in gastric motor activity in conscious dogs.

Twenty-four-hour changes in gastric motor activity were recorded in 4 healthy adult dogs in the conscious state by means of extraluminal force transducers. Three major different gastric motor activity patterns were recognized during 24 hr: digestive, intermediate, and interdigestive. The digestive pattern was characterized by steady low-amplitude contractions in the gastric antrum, with no significant motor activity in the gastric body. The interdigestive pattern consisted of series of high-amplitude contractions of 14-23 min duration in both the gastric body and antrum with intervening and long-lasting (68-109 min) motor quiescence. The intermediate pattern is considered to be the pattern midway when the digestive pattern is changing to the interdigestive pattern. These changes in gastric motor activity are precisely controlled day after day if the animals are fed at regular time intervals and are healthy. The digestive pattern may represent principally a mixing function of ingested food and the interdigestive pattern a cleaning function in preparation for the next meal