title: A circulatory model for calculating non-steady-state glucose fluxes. Validation and comparison with compartmental models.
abstract: This study presents a circulatory model of glucose kinetics for application to non-steady-state conditions, examines its ability to predict glucose appearance rates from a simulated oral glucose load, and compares its performance with compartmental models. A glucose tracer bolus was injected intravenously in rats to determine parameters of the circulatory and two-compartment models. A simulated oral glucose tolerance test was performed in another group of rats by infusing intravenously labeled glucose at variable rates. A primed continuous intravenous infusion of a second tracer was given to determine glucose clearance. The circulatory model gave the best estimate of glucose appearance, closely followed by the two-compartment model and a modified Steele one-compartment model with a larger total glucose volume. The standard one-compartment model provided the worst estimate. The average relative errors on the rate of glucose appearance were: circulatory, 10%; two-compartment, 13%; modified one-compartment, 11%; standard one-compartment, 16%. Recovery of the infused glucose dose was 93+/-2, 94+/-2, 92+/-2 and 85+/-2%, respectively. These results show that the circulatory model is an appropriate model for assessing glucose turnover during an oral glucose load.
authors.affiliation: Institute of Systems Science and Biomedical Engineering, National Research Council, LADSEB-CNR, Corso Stati Uniti 4, 35127 Padova, Italy. mari@ladseb.pd.cnr.it
authors.forename: Andrea
authors.initials: A
authors.lastname: Mari
authors.forename: L
authors.initials: L
authors.lastname: Stojanovska
authors.forename: J
authors.initials: J
authors.lastname: Proietto
authors.forename: A W
authors.initials: AW
authors.lastname: Thorburn
mesh_terms: D000818:Animals; D001786:Blood Glucose / Q000378:metabolism*; D008297:Male; D008954:Models, Biological; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D001786:Blood Glucose