AJP - Gastrointestinal and Liver Physiology, Vol 269, Issue 3 363-G369, Copyright © 1995 by American Physiological Society
Effects of ethanol, xylose, and glucose on canine jejunal motility
F. Charles and S. F. Phillips
Gastroenterology Research Unit, Mayo Clinic, Rochester, Minnesota 55905, USA.
Ethanol is an important source of calories that can cause certain
gastrointestinal symptoms, notably diarrhea. To examine the effects of
ethanol on the small bowel, we intraluminally perfused the jejunum of four
dogs with ethanol (18, 9, 4.5, and 1.5%, wt/vol), D-xylose (30, 15, 7.5,
and 4.5%, wt/vol), or glucose (30 and 5%, wt/vol). In other experiments,
these solutes were infused intravenously. Saline was always given by the
alternate route; jejunal manometry was recorded during and after the
infusions. Phase III of the interdigestive cycle was delayed by all
intraluminal infusions except for 4.5 and 1.5% ethanol, 4.5% xylose, and 5%
glucose. In addition, the onset of irregular contractile activity was
delayed more with intraluminal ethanol than with intraluminal xylose or
intraluminal glucose (P < 0.01). When administered intraluminally,
ethanol and xylose appeared in blood but only ethanol equilibrated fully
between the lumen and blood. Intravenous infusions of ethanol and xylose,
but not glucose, also delayed the return of phase III. When given
intravenously, ethanol and xylose were recovered from the lumen, whereas
glucose never was. Ethanol and xylose had comparable effects on the canine
small bowel; they induced prolonged periods of irregular contractile
activity and delayed the return of phase III. These effects were seen
rapidly when solutes were administered intraluminally and more slowly when
they were given intravenously. These results suggest that local luminal
mechanisms stimulated by solutes influence small bowel motility, and they
imply that the gut recognizes solutes whether or not these molecules are
metabolizable.
