Effects of Posture on Gastric Emptying, Transpyloric Flow, and Hunger After a Glucose Drink in Healthy Humans

Abstract

Previous studies suggest that posture has relatively little effect on gastric emptying of high-nutrient liquids; these studies have, however, only assessed overall rates of gastric emptying, whereas gastric emptying is known to be predominantly a pulsatile phenomenon. In healthy subjects perceptions of appetite, such as hunger, are inversely related to antral area and content; hence, changes in intragastric meal distribution induced by posture may affect appetite. Gastric emptying is a major determinant of postprandial glycemia. The aims of this study were to evaluate the effects of posture on patterns of transpyloric flow (TF), gastric emptying (GE), antral area (AA), hunger, and the glycemic response to oral glucose. Eight healthy young subjects (five males, three females; mean age, 24.0 +/- 2.4 years; BMI, 21.2 +/- 0.6 kg/m2) were studied twice in random order, once in the sitting position and once in the lying (supine) position. After consuming 600 ml water with 75 g glucose, labeled with 20 MBq 99mTc-sulfur colloid, subjects had simultaneous measurements of (i) TF during consumption of the drink by Doppler ultrasonography, (ii) GE with scintigraphy, (iii) AA at t = -5 and t = 30 min by ultrasonography, and (iv) perceptions of appetite with a visual analogue scale. During drink ingestion TF was greater in the sitting, compared with the lying, position (586 +/- 170 vs. 177 +/- 65 [cm/sec] x sec; P < 0.05). Posture affected intragastric distribution; more of the drink was retained in the distal stomach in the sitting position (e.g., at 30 min: sitting, 29 +/- 3%, vs. lying, 12 +/- 3%; P < 0.0001) but had no effect on the overall rate of GE or the blood glucose response. AA at t = 30 min (P < 0.005) was greater in the sitting position; there was an inverse relationship between hunger and AA at 30 min (r = -0.53, P < 0.05). We conclude that posture influences initial TF and intragastric distribution, but not the overall rate of GE of, or the glycemic response to, a large-volume nutrient liquid. The increases in AA and content in the sitting position are associated with a reduction in hunger.

Influence of posture on pharmacokinetics

“…In the trial cited above, BurnMurdoch et al did not find any significant influence of posture on the emptying rate of 750 ml of a glucose drink. Despite the force of gravity being the same for both kinds of liquids, corresponding studies confirmed this difference [6,7]. Whereas intragastric volume and gravity appear to be the driving forces controlling gastric emptying of nonnutrient liquids [2,5,8], for nutrient liquids, feedback from small intestinal "nutrient" receptors is the decisive factor.…”

“…glucosecontaining drinks or olive oil), the effects of changes in posture are much less pronounced than those for non-or low-nutrient liquids (e.g. saline or low-nutrient beef consommé soup) [4,5,7]. In the trial cited above, BurnMurdoch et al did not find any significant influence of posture on the emptying rate of 750 ml of a glucose drink.…”

“…After ingestion of a 600-ml glucose test drink, hunger and prospective consumption were significantly less in the sitting position than in the supine position, continuously from 45 min until the end of the observation period 180 min after ingestion [7]. Horowitz et al found a reduction of hunger in the left lateral decubitus position compared to sitting.…”

Bioequivalence Study of Two Formulations Containing Bosutinib 500 mg Tablets in Healthy Colombian Volunteers

“…Previously labelled tube was transferred with Plasma and frozen at -20°C for analysis later. After 15 day washout period, deliverance was done again after the completion of the second study period [4].…”

Ultrasonography of the Stomach

“…Whilst there are substantial operational and technical demands of this type of ultrasound, the significant insight into the normal physiological movements involved in digestion it provides has proven invaluable in the research setting (King et al, 1984;Hausken et al, 1998a;Jones et al, 2006). Transpyloric flow has been shown to be greater in a sitting position, compared to a supine position, with no effect on the overall emptying of a standardised drink consisting of 600mL of water and 75g of glucose .…”