The pressure profile of the gastroduodenal junctional zone in dogs

Abstract

In healthy, unanesthetized fasting dogs, a zone of elevated pressure was detected in the gastroduodenal junction in 60% of studies with a lateral orifice tube 1.7 mm in diameter and with increasing incidence in 80 and 97% with progressively larger balloons, to 7X7 mm. The mean maximal pressure recorded in the junction with different detectors ranged from 3.2-11.3 cm of water, depending on their cross-sectional diameter. The mean width of the zone varied only from 1.1-1.6 cm. During introduction of 48 ml 0.1 N HCl into the duodenum for 8 minutes, duodenal activity and mean maximal pressure increased in the junction while antral motility decreased. During instillation of 16 ml olive oil for 8 minutes, no significant change was noted in mean pressures in the junction, although antral activity was inhibited. Fifteen-20 minutes later, the mean maximal pressures were increased in the junction, and antral activity remained inhibited.