Wash-in methodology and modeling to determine hepatocellular D-glucose transport in the perfused rat liver.
Wash-in experiments, which may be useful for the study of the disposition of substrates in the liver, have not been well described. To investigate physiological models for wash-in curves, we performed experiments on the perfused livers of male Wistar rats anesthetized with pentobarbital. Test perfusate contained (14)C-sucrose as the extracellular marker and (3)H-glucose. Liver perfusions were performed with background glucose concentrations of 5.7, 10.7, 51.2, or 108.5 mM. Outflow time-activity curves were analyzed with the use of four models. The V(max) and K(m) for the influx of glucose were 1.1 +/- 0.03 micromol/s/g and 41 +/- 3 mM with the Crone-Renkin early extraction model; 1.4 +/- 0.04 micromol/s/g and 36 +/- 3 mM with dispersion model analysis; 1.8 +/- 0.1 micromol/s/g and 25 +/- 4 mM with the Goresky distributed model to fit differentiated wash-in curves; and 2.7 +/- 0.6 micromol/s/g and 28 +/- 21 mM with compartmental analysis. There was reasonable agreement between the four models, and they yielded results similar to those reported for glucose uptake in other preparations.
Le Couteur
D G
DG
Centre for Education and Research on Aging, ANZAC Research Institute, Concord RG Hospital, The University of Sydney, Australia. dlecouteur@med.usyd.edu.au
Yin
Z L
ZL
McLean
A J
AJ
Rivory
L P
LP
D000818:Animals; D005947:Glucose / Q000493:pharmacokinetics*; D008099:Liver / Q000098:blood supply / Q000502:physiology*; D008297:Male; D008962:Models, Theoretical; D051381:Rats; D017208:Rats, Wistar; D015203:Reproducibility of Results; D013549:Sweetening Agents / Q000493:pharmacokinetics*
D013549:Sweetening Agents; D005947:Glucose