title: Human duodenal phase III migrating motor complex activity is predominantly antegrade, as revealed by high-resolution manometry and colour pressure plots.
abstract: Abstract Late phase III migrating motor complex activity has been said to be primarily retroperistaltic but has not been assessed with high resolution manometry or three-dimensional colour pressure plots (pressure/time/distance). Duodenal phase III was examined in healthy young volunteers (seven male, two female) with a 20-lumen assembly. With the most proximal sidehole in the distal antrum, after a 4.5-cm interval 18 sideholes at 1.5-cm intervals spanned the duodenum with a final sidehole 3 cm beyond. Fasting pressures were recorded until phase III occurred. Comparisons were made between proximal (P) and distal (D) duodenum during early (E) (first 0.5-1 min) and late (L) (last 0.5-1 min) phase III. With colour pressure analysis, 121 of 180 pressure wave (PW) sequences were purely antegrade, two purely retrograde and 57 bidirectional. Ten of fifty-seven bidirectional PW sequences were complex, branching to become two separate sequences. Bidirectional sequences occurred more frequently in late than early phase III (L 43 vs. E 14 of 57), but their occurrence did not differ between proximal and distal duodenum (P31 vs. D 24 of 57). Antegrade propagation velocity was faster in late compared with early phase III (L 28.50 vs. E 17.05 mm s(-1); P = 0.006), but did not differ between proximal and distal duodenum. Colour pressure analysis also indicated an intermittent segmental pattern to phase III, with each subject exhibiting a change in velocity or direction, or a relative failure of peristalsis somewhere along the duodenum during part of phase III. Duodenal phase III is not homogenous and, in contrast with previous studies, does not primarily constitute a retroperistaltic pump. Colour pressure analysis is useful in interpreting intraluminal pressure profiles and may improve the sensitivity and specificity of clinical studies.
authors.affiliation: University Department of Medicine, and Department of Gastroenterology, Hepatology and General Medicine, Royal Adelaide Hospital, Adelaide Division of Medicine, Repatriation General Hospital, Daw Park, Australia. jane.andrews@adelaide.edu.au
authors.forename: J M
authors.initials: JM
authors.lastname: Andrews
authors.forename: D G
authors.initials: DG
authors.lastname: O'donovan
authors.forename: G S
authors.initials: GS
authors.lastname: Hebbard
authors.forename: C H
authors.initials: CH
authors.lastname: Malbert
authors.forename: S M
authors.initials: SM
authors.lastname: Doran
authors.forename: J
authors.initials: J
authors.lastname: Dent
mesh_terms: D000328:Adult; D016009:Chi-Square Distribution; D004386:Duodenum / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008365:Manometry / Q000295:instrumentation / Q000379:methods; D016065:Myoelectric Complex, Migrating / Q000502:physiology*; D010528:Peristalsis / Q000502:physiology; D011312:Pressure