Glucose fluxes during OGTT in adolescents assessed by a stable isotope triple tracer method.
Virtually no information is available on glucose fluxes during a meal or glucose ingestion in adolescents.


OBJECTIVE
To use a triple tracer approach to measure rates of appearance of ingested glucose (Ra(ogtt)), endogenous glucose production (EGP) and glucose disappearance (Rd) following an oral glucose bolus in adolescents.


METHODS
Eleven adolescents (4 M/7 F, 15 +/- 1 yr; 67.3 +/- 4.7 kg; 24 +/-2 kg/m2) underwent a frequent sampled oral glucose tolerance test (OGTT) (labelled with [6,6-2H2]glucose) combined with intravenous infusion of [1-(13)C]glucose and [U-(13)C6]glucose following an overnight fast. Formulas were developed to estimate glucose fluxes using one- or two-compartment models.


RESULTS
During the 7 h following the OGTT bolus, 9.8 +/- 2.3% of the ingested glucose was extracted by the liver, EGP was suppressed by 45 +/- 4% and Rd increased by 21 +/- 5%.


CONCLUSIONS
The triple tracer method provided accurate assessment of Ra(ogtt), EGP and Rd fluxes during an OGTT in adolescents. Thus, this method might provide novel insight on postprandial glucose fluxes in children/adolescents under various conditions.
Toffolo
Gianna
G
Department ofl Information Engineering, University of Padova, Padova, Italy.
Dalla Man
Chiara
C
Cobelli
Claudio
C
Sunehag
Agneta L
AL
D000293:Adolescent; D000375:Aging / Q000378:metabolism; D001786:Blood Glucose / Q000378:metabolism*; D002247:Carbon Isotopes; D003903:Deuterium; D003920:Diabetes Mellitus / Q000097:blood / Q000175:diagnosis*; D005260:Female; D005947:Glucose / Q000378:metabolism; D005951:Glucose Tolerance Test / Q000379:methods*; D006801:Humans; D008297:Male; D008954:Models, Biological; D011849:Radioactive Tracers; D014316:Tritium
D001786:Blood Glucose; D002247:Carbon Isotopes; D011849:Radioactive Tracers; D014316:Tritium; D003903:Deuterium; D005947:Glucose