Effects of oral vs i.v. glucose administration on splanchnic and
extra-splanchnic oxygen uptake and blood flow.
Brundin, Tomas, Robert Br[umlaut]anstr[diaeresis]om, and John Wahren.
Department of Clinical Physiology, Karolinska Hospital, S-171 76
Stockholm, Sweden
APStracts 3:0097E, 1996.
The metabolic and circulatory responses to intravenous (i.v.) or oral
administration of glucose (75 g) were studied in healthy subjects.
Pulmonary oxygen uptake increased promptly after oral but not during
i.v. glucose infusion. The average 2 h rise above basal in whole body
oxygen uptake was 8+/-1 % (P<0.001) after oral glucose and 3+/-1
% (P<0.05) during i.v. glucose infusion. After oral glucose,
splanchnic oxygen uptake rose initially by approximately 15 %
(P<0.01) and then declined; its average 2 h postprandial level
was not significantly higher than that in the basal state. During
i.v. glucose, splanchnic oxygen uptake decreased gradually during the
first 75 min, reaching a level approximately 25 % below the basal
(P<0.05). Oxygen consumption by extra-splanchnic tissues rose
significantly and to a similar extent (8 %, 2 h average) with both
i.v. and oral glucose. Splanchnic blood flow increased significantly
after oral but not during i.v. glucose. It is concluded that a) i.v.
and oral glucose administration elicit extra-splanchnic thermogenic
effects of similar magnitude, b) during i.v. glucose infusion the
extra-splanchnic thermogenic effect is counterbalanced by a
simultaneous reduction in splanchnic oxygen uptake, resulting in a
minimal (3 %) net rise in whole body oxygen uptake, and c) oral
glucose ingestion but not i.v. glucose infusion increases the
splanchnic blood flow.
Received 20 February 1996; accepted in final form 24 April 1996.
APS Manuscript Number E86-6.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 19 May 96