Intraluminal pressure of the small intestine of the unanesthetized dog.
Intraluminal pressure recordings have been performed in 14 unanesthetized dogs via a Mann-Bollman fistula by means of an air-filled balloon catheter system and a water-filled catheter system. The dynamic response is adequate for studying intraluminal pressures of the small intestine. Resting pressures in the proximal, middle and distal jejunum averaged approximately 6 mm Hg above atmosphere and no appreciable differences were noted between the different areas. The contraction time of simple, monophasic waves was fairly constant (approximately 1.0 s in duration) and usually unrelated to amplitude of the wave. Propulsion of intraluminal contents occurred in the absence of complex (type III) waves. A pressure wave in a proximal segment of jejunum was temporally related to a wave occurring 5 cm distally. The mean intervals between the proximal and distal contractions were: 0.42 s in the proximal jejunum; 0.74 s in the middle jejunum; 1.56 s in the distal jejunum; 2.79 s in the ileum. These time lags have a log normal distribution. The length of the physiologic segment in the jejunum of the dog varied from 1.0-8.0 cm and was usually 2-4 cm.
D000818:Animals; D002404:Catheterization / Q000379:methods; D004285:Dogs; D005260:Female; D005769:Gastrointestinal Motility; D007082:Ileum / Q000502:physiology; D007421:Intestine, Small / Q000502:physiology*; D007583:Jejunum / Q000502:physiology; D008722:Methods; D011312:Pressure; D014159:Transducers