The relationship of the sphincter of Oddi to the stomach, duodenum and gall-bladder.

Flow through the sphincter of Oddi was studied by a constant-pressure perfusion apparatus, and by using a constant rate of infusion and measuring pressure changes just proximal to the sphincter. Pressure changes from balloons placed in the gastric antrum and duodenum were recorded. Despite considerable variation in activity and behaviour, the following conclusions were reached.1. The sphincter of Oddi appears to be partially autonomous but is readily affected by changes in duodenal tone.2. Reflex inhibition of the sphincter of Oddi is seen on electrical and mechanical stimulation of the gall-bladder but not with passive pressure changes within the gall-bladder.3. This reflex is relayed through the coeliac ganglion.4. There is a definite relationship between gastric antral activity and flow through the sphincter of Oddi. This is more obvious when food is present in the stomach.5. Mechanical or electrical stimulation of the stomach, duodenum, or upper small bowel influences the tone of the sphincter of Oddi.