Pyloric motility. Sleeve sensor versus strain gauge transducer.

Intraduodenal infusion of nutrients has been shown by intraluminal sleeve-sidehole manometry to suppress antral contractions and stimulate isolated pyloric pressure waves (IPPWs) in humans. It is still unresolved, whether these pyloric contractions occur within an otherwise quiescent zone of motor and electrical activity and whether the presence of the sleeve sensor itself affects this nutrient-associated response. In four conscious dogs, comparisons were made between paired recordings of myoelectrical and motor activities of the antropyloroduodenal region with serosal strain gauge transducers and extracellular bipolar electrodes in the presence and absence of an intraluminal manometric sleeve-sidehole assembly during intraduodenal infusions of saline and a triglyceride emulsion (Intralipid 10%, 0.5 kcal/min). Of 287 isolated pyloric pressure waves, detected by the manometric sleeve sensor, 75% were detected as isolated pyloric contractions by the strain gauge transducers and 72% occurred in the absence of electrical spike activity in the distal antrum or proximal duodenum. The lower incidence of isolated pyloric contractions (strain gauges) was related to: (1) insensitivity of the pyloric strain gauge transducer in comparison to the manometric sleeve sensor (10%), and (2) inability of the manometric sleeve-sidehole assembly to detect pressure waves in the distal antrum (7%) or proximal duodenum (8%) during antral or duodenal wall motion. The presence of the sleeve sensor itself did not affect the number of lipid-induced isolated pyloric contractions but increased their amplitude [median 9 (7-15) mN vs 4 (2-6) mN; P < 0.05].(ABSTRACT TRUNCATED AT 250 WORDS)