[Diabetes diagnosis following intravenous and oral glucose load: animal experiment principles]

Aiming at highest possible reduction of causes of individual variability, at determination of diagnostic value of different intravenous and oral (intragastric, per sondam) glucose loads and at comparison of diagnostic value of ivGTT and oGTT after the same load, author first performed ivGTT with 1 g glucose per kg body mass and oGTT with 1, 2, 4 g/kg in normal (non anaesthesized) adult (F 6-7) inbred rats and mice and than repeated these tests with the same loads and the same rats and mice with different extent of B-Cell lesion after i.v. alloxan injection. Results show that for unmasking of latent ("chemical") diabetes a higher load (4 g/kg orally) was necessary, that the assimilation constant of ivGTT was diabetic earlier than the criteria of oGTT after equal oral load (1 g/kg) and that for the diagnosis of early stages of diabetes not only absolute values of GTT curves but also their form are important.