[Characteristics of the functional compartmentation of the small intestine. Study at the duodenal level in the rat].

A radiological study using the conscious rat (n = 23) showed the different putative compartments at the duodenal level. We report here the in vitro pressure-volume-time of two compartments. The first one extended 0 to 1.7 cm +/- 0.3 from the pylorus, while the second one included the junction with the common biliopancreatic duct. The significant results showed that the first compartment had relative stretch with predominant pendulum motility; the threshold stretch for the onset of this motility was 58 p. 100 of the mean maximum diameter. It thus appeared to have a capacitive function, whereas the second compartment acted as a propulsion system in which the threshold stretch for peristalsis was 29 p. 100 of the mean maximum diameter.