A study of motility of normal human gastroduodenal region

Abstract

A method of recording continuously and simultaneously the intraluminal pressure in the antrum, pylorus, and duodenal bulb has been used to study gastroduodenal motility during intragastric infusion of saline. Twenty-two studies were performed in 15 normal individuals. Two types of contraction were recorded: (1) independent contractions of the individual parts of the gastroduodenal region, and (2) related contractions of the antrum, pylorus, and duodenal bulb, resulting in a concerted contraction of the whole region. The majority of pyloric contractions were part of a concerted contraction of the whole gastroduodenal region during which the pylorus behaved as the terminal part of the antrum. The majority of duodenal contractions were not associated with pyloric contractions, only 21.7% of duodenal contractions coincided with closure of the pylorus. This suggests that under the conditions of this study the pylorus was not acting as a barrier to reflux. An elevated basal pressure was never recorded from within the pylorus; apart from a brief closure during contraction, the pylorus is always open.

Functional association between proximal and distal gastric motility during fasting and duodenal nutrient stimulation in humans

“…Once gastric contents arrive in the antrum, the characteristics of antral waves are likely to dictate the functional outcome. Intermittent isolated antral waves are primarily responsible for the mixing and breakdown of food boluses, 11 whilst PAWs triturate contents in the presence of a closed pylorus and clear the content into the duodenum if the pylorus is open 13 . Several findings in the current study are consistent with this concept.…”

“…On the other hand, the distal stomach regulates the rate of gastric emptying of both liquid and solid meals, 1,2,4,9 via a highly coordinated process involving the antrum, pylorus and duodenum 10,11 . It is generally believed that intermittent isolated antral waves against a closed pylorus are primarily responsible for mixing and breakdown of food boluses, 11 whilst peristaltic antral wave activity plays a major role in the movement of distal gastric content into the duodenum 12,13 …”

Review article: gastrointestinal angiodysplasia - pathogenesis, diagnosis and management

“…This applies to the ascending colon and caecum (large diameter with thin wall) where the bowel wall tension is highest, which compresses the submucosal venules, but not arterioles. A similar mechanism takes place in the gastric antrum and pylorus where muscle contraction is most vigorous leading to the development of ectatic vessels and AD …”

Gastric emptying and the organization of antro‐duodenal pressures in the critically ill

“…In health, gastric emptying (GE) occurs predominantly in a pulsatile fashion, the characteristics of which are dependent on the integration of motor activity in the proximal and distal stomach and proximal small intestine 1–3 . Antro‐pyloro‐duodenal (APD) activity is characterized by either intermittent isolated pressures which vary in frequency and amplitude, or coordinated propagated (peristaltic) pressure waves which move varying distances through the antrum, across the pylorus and into the duodenum 4 . Intermittent, isolated pressures appear to be primarily responsible for the mixing and breakdown of food boluses, while transpyloric flow occurs as a result of peristaltic or non‐peristaltic APD gradients; 5,6 the latter are formed by changes in basal antral, relative to duodenal, pressure.…”