RELATIONSHIPS BETWEEN CECOILEAL REFLUX AND ILEAL MOTOR PATTERNS IN CONSCIOUS PIGS

Ileal infusion of cecocolonic contents, used to mimick reflux, enhance d terminal ileal motility, increasing the frequencies of prolonged pro pagated contractions (PPC) and discrete clustered contractions (DCC). Because the reflux rate in dogs and humans is marginal, the relationsh ip of these motor patterns to reflux remained putative. In six conscio us pigs, the ileal pH, used to indicate reflux event, was measured 10 and 5 cm proximal to the ileocecal sphincter (ICS). Ileal motility was evaluated with three strain gauges 15, 10, and 5 cm proximal to the I CS. Ileal pH dips were observed about eight times per hour in the fast ing or fed state, and 46% of the pH dips were preceded by a retrograde contraction. During pH dips, frequency of ileal contractions not clas sified as PPC or DCC was significantly increased. Of the PPC 52% occur red immediately after the start of the dip and might act as a clearanc e mechanism because dips associated with PPC were of smaller amplitude and duration than those not associated with PPC. Most DCC also occurr ed during pH dips but their delay to the onset of the dip was longer. The pig presents frequent cecoileal reflux events associated with ilea l motor patterns, some of them might facilitate reflux, whereas others act as a clearance mechanism.