ANALYSIS OF DUODENAL CONTRACTILITY IN THE UNANESTHETIZED DOG

The temporal relationship of circular muscle contractions at eight positions spaced at 2.5 cm intervals along the duodenum was determined after administration of test meals and drugs in dogs chronically implanted with strain-gage force transducers. An automatic data analysis system was developed to 1) recognize contractions, 2) measure contractile amplitudes and intercontractile intervals, 3) perform statistical calculations, and 4) present results in various different formats. Under virtually all test conditions, when propagated contractions were present, the mean propagation was in a caudad direction. Two specific results indicate that after feeding, duodenal contractions produce a greater mixing action. The percentage of contractions which were propagated between adjacent transducer locations was significantly (p < 0.05) decreased from that of an interdigestive state when the animals received canned dog food. The minimum interval between contractions at a particular transducer position increased significantly (p < 0.05) from that of an interdigestive stage when a citrate plus fat test meal was administered. © 1979 SDAIEEE