MEASUREMENT OF POST-ABSORPTIVE GLUCOSE KINETICS IN NON-INSULIN-DEPENDENT DIABETIC-PATIENTS - METHODOLOGICAL ASPECTS

Post-absorptive glucose metabolism was studied in non-insulin-dependen t diabetes mellitus (NIDDM) patients and normal subjects using dideute rated glucose as tracer. From the progressive fall in blood glucose le vels and the increase in isotopic enrichment, the post-absorptive situ ation could not be regarded as a steady state for glucose metabolism, and non-steady-state approximations had therefore to be applied. Howev er, this did not alter significantly the results in the 10 NIDDM patie nts studied. Significantly higher values of endogenous glucose product ion (EGP) were obtained (178.1 +/- 24.0 mg m(-2) min(-1) vs. 80.2 +/- 14.4; P < 0.01) if the tracer priming dose was not adapted to the degr ee of hyperglycaemia. Valid measurements could be made after only Ih i sotopic equilibration time if an appropriately matched priming dose wa s employed. Methodologically acceptable values for EGP in the 10 NIDDM patients did not differ significantly from those of 10 normal control subjects (80.2 +/- 14.4 mg m(-2) min(-1) vs. 856 +/- 3.9; not signifi cant). The post-absorptive hyperglycaemia in these patients was assume d to stem essentially from a defect in peripheral glucose uptake.