Esophago-rectal reflex. Description and clinical significance.

The present communication describes the "esophago-rectal reflex" and its clinical significance. The study was performed in 19 healthy volunteers and 14 constipated subjects. The technique comprised the introduction into the esophagus of a balloon-tipped tube so that the balloon lay within the lower esophageal sphincter (LES). The rectal and rectal neck pressures were measured by means of perfused open-ended tubes. The esophageal balloon was inflated with 2, 4 and 6 ml water and the responses of the rectal and rectal neck pressures were recorded. Distension of the LES was accompanied by significant rectal pressure increase (P < 0.001); the pressure increased with increasing LES distension. Anesthetized LES mucosa did not evoke the rectal pressure response. The rectal neck pressure did not show significant change with LES distension (P > 0.05). Both the rectal and rectal neck pressures showed insignificant response to LES distension in constipated subjects (P > 0.05). The esophago-rectal reflex seems to be conducted through the myenteric plexus from the esophagus down along the gut wall to the rectum, initiating rectal contractions. It is likely that these signals alarm the rectum for the entrance of new contents in the gut so that the rectum may evacuate its contents.