Glucose production during exercise in humans: a-hv balance and isotopic-tracer measurements compared.
The present study compared the arteriohepatic venous (a-hv) balance technique and the tracer-dilution method for estimation of hepatic glucose production during both moderate and heavy exercise in humans. Eight healthy young men (aged 25 yr; range, 23-30 yr) performed semisupine cycling for 40 min at 50.4 +/- 1.5(SE)% maximal O(2) consumption, followed by 30 min at 69.0 +/- 2.2% maximal O(2) consumption. The splanchnic blood flow was estimated by continuous infusion of indocyanine green, and net splanchnic glucose output was calculated as the product of splanchnic blood flow and a-hv blood glucose concentration differences. Glucose appearance rate was determined by a primed, continuous infusion of [3-(3)H]glucose and was calculated by using formulas for a modified single compartment in non-steady state. Glucose production was similar whether determined by the a-hv balance technique or by the tracer-dilution method, both at rest and during moderate and intense exercise (P > 0. 05). It is concluded that, during exercise in humans, determination of hepatic glucose production can be performed equally well with the two techniques.
Department of Physical Education, University of Montreal, Montreal, Quebec, Canada H3C 3J7.
R
R
Bergeron
M
M
Kjaer
L
L
Simonsen
J
J
Bülow
H
H
Galbo
D000328:Adult; D004396:Coloring Agents; D005069:Evaluation Studies as Topic; D015444:Exercise / Q000502:physiology*; D005947:Glucose / Q000096:biosynthesis*; D006801:Humans; D007208:Indocyanine Green; D008099:Liver / Q000378:metabolism; D008297:Male; D010101:Oxygen Consumption; D013152:Splanchnic Circulation; D014316:Tritium
D004396:Coloring Agents; D014316:Tritium; D007208:Indocyanine Green; D005947:Glucose