Spatiotemporal organization of standing postprandial contractions in the distal ileum of the anesthetized pig. Issue 11 (24th September 2014)

• Record Type: Journal Article
• Authors: Janssen, P. W. M.; Lentle, R. G.; Chambers, P.; Reynolds, G. W.; De Loubens, C.; Hulls, C. M.
• Is Part Of: Neurogastroenterology & motility. Volume 26:Issue 11(2014:Nov.)
• Page Start: 1651
• Page End: 1662
• Publication Date: 2014-09-24
• Subjects: Gastrointestinal system -- Motility -- Periodicals; Gastrointestinal system -- Innervation -- Periodicals; 616.33
• DOI: 10.1111/nmo.12447
• Languages: English
• ISSNs: 1350-1925

Abstract

<abstract abstract-type="main" id="nmo12447-abs-0001"> <title>Abstract</title> <sec id="nmo12447-sec-0001" sec-type="section"> <title>Background</title> <p>Spatiotemporal (ST) mapping has mainly been applied to <italic>ex vivo</italic> preparations of the gut. We report the results of ST mapping of the spontaneous and remifentanil‐induced motility of circular and longitudinal muscles of the distal ileum in the postprandial anaesthetized pig.</p> </sec> <sec id="nmo12447-sec-0002" sec-type="section"> <title>Methods</title> <p>Spatiotemporal maps of strain rate were derived from image sequences of an exteriorized loop of ileum on a superfusion tray at laparotomy. Parameters were obtained by direct measurement from these maps, and by auto‐ and cross‐correlation of map segments.</p> </sec> <sec id="nmo12447-sec-0003" sec-type="section"> <title>Key Results</title> <p>Localized domains of standing longitudinal and circular activity that alternated between neighboring domains occurred spontaneously and both were promptly extinguished following intraluminal dosage with lidocaine. Longitudinal or circular contractions within a domain typically occurred at times that would coincide with every second or third cycle of the slow wave but propagated within the domain at a rate consistent with that reported within spike patches. Shortly after intravenous administration of remifentanil, longitudinal and circular contractions at the reported slow wave frequency propagated over longer distances at a high speed before slowing to a rate similar to that reported for slow waves.</p> </sec> <sec id="nmo12447-sec-0004" sec-type="section"> <title>Conclusions & Inferences</title> <p>ST mapping based on cross‐correlation is a robust tool for the analysis of intestinal movement and minimizing movement artefacts. We propose that the ST pattern of standing longitudinal and circular contractions arises from variation in the refractory period of smooth muscle, and hence, in its response to successive slow waves with neural stimuli influencing the former and having a mainly permissive role.</p> </sec> </abstract>