Effect of the osmolality of caloric and acaloric liquids on gastric myoelectrical activity in humans.
BACKGROUND
The aim was to establish the effect of the osmolality of orally consumed liquids on gastric myoelectrical activity (GMA).


METHODS
Twenty-five healthy volunteers (13 women, 12 men aged 29.4+/-1.4 [SE] years) underwent five examinations on separate days. After a 20-min basal electrogastrographic recording, the volunteers drank 400 ml of a) bi-distilled water, b) 0.9% NaCl, osmolality 286 mmol/kg, c) 2.9% NaCl, osmolality 827 mmol/kg, d) 5% glucose, osmolality 282 mmol/kg, energy density 209 kcal/l, or e) 15% glucose, osmolality 836 mmol/kg, 627 kcal/l. Then the registration of GMA was continued for 60 min. Gastric emptying was measured with the 13C-acetate breath test.


RESULTS
Compared with distilled water, the isotonic glucose drink elicited a positive chronotropic influence on and stabilization of GMA. At the transition from isotonicity to hypertonicity, a pronounced destabilization of GMA was observed, with opposite directions of changes brought about by the presence or absence of a caloric load; bradygastria was manifested after the energy-free hypertonic NaCl solution whereas hypertonic glucose evoked a tachygastric pattern. A marked delay in gastric emptying was found with both hypertonic drinks.


CONCLUSIONS
Osmolality and its interplay with chemical composition/energy density must be taken into account when choosing a test meal for an electrogastrographic examination and interpreting its results. Of the five fluids examined, isotonic glucose appeared to be the drink least disturbing to GMA.
Syrkiewicz-Trepiak
Danuta
D
Department of Basic Biomedical Science, School of Pharmacy, Medical University of Silesia, Sosnowiec, Poland.
Jonderko
Krzysztof
K
Kasicka-Jonderko
Anna
A
D000328:Adult; D002149:Energy Intake; D005260:Female; D005746:Gastric Emptying; D006801:Humans; D008297:Male; D009994:Osmolar Concentration; D016037:Single-Blind Method; D013270:Stomach / Q000502:physiology*