Digestive motor patterns and transit of luminal contents in canine ileum.

In the present study ileal motor patterns caused by orally administered noncaloric and nutrient meals were investigated. Effects of nutrients were additionally elucidated by an ileal infusion of nutrients. Conscious dogs equipped with closely spaced extraluminal transducers were used. Motor patterns were quantified by a computerized method. Transit rates were measured fluoroscopically. Compared with the motor pattern caused by the noncaloric meal, the nutrient meal diminished the number of contractions from 11.7 to 5.9/min, reduced the incidence of contraction waves from 70.8 to 39.4%, shortened the length of contraction spread from 4.0 to 1.4 cm, and slowed the transit rate from 18.4 to 3.2 cm/min. Ileal infusion of nutrients induced a motor pattern similar to that of the nutrient meal. The transit rate correlated with the length of contraction spread (r = 0.75), the ratio between contraction waves and stationary contractions (r = 0.77), and the number of contractions (r = 0.69). The length of contraction spread was the most characteristic feature of motor patterns and the most important factor influencing transit.