[Effect of antidiabetics on post-exercise alaninemia in patients with non-insulin-dependent diabetes mellitus (type 2)].

A group of 15 patients with controlled insulin-independent diabetes (Type 2) were workloaded submaximally by a 15-minute load on a cycle ergometer and 2-3 days later same workload was repeated, but this time 5-patient groups were administered before the workload: 0.1 j.m. of insulin/kg of body mass i.v., 1.0 g tolbutamide sodium i.v. and 150 mg of phenformin orally one hour before the load. The patients who were injected insulin or tolbutamide were also administered glucose solution (intravenously) so as to keep the same level of glycaemia as in the follow-up examination. The time of metabolic observation after workload was 90 min., so the whole examination took 105 minutes. In the first (follow-up) examination, all the probands had in the venous blood an increase in alanine, lactate, pyruvate and the relation lactate: pyruvate (L/P), a decrease in pH, bicarbonates and pO2 (in capillary afterialized blood). The administration of insulin and tolbutamide eliminated or reduced after-effort alaninaemia increase, whereas the administration of phenformin increased the concentration of this amino acid in the blood after effort. Insulin resulted in a greater increase in after-effort lactacidaemia; besides, insulin and tolbutamide increased the relation L/P during and after effort. The influence of antidiabetic drugs on the behaviour of other biochemical parameters after effort was insignificant. The results obtained show that antidiabetic drugs modify the increase in alaninaemia after effort in patients with controlled insulin-independent diabetes (Type 2), the direction of the modification depending on a specific influence of particular drugs on the metabolism of this amino acid. While evaluating the influence of effort on the concentration of alanine in the blood in patients with this type of diabetes one should consider not only the present demand for this gluconeogenes substrate but also a specific influence of the kind of therapy applied at the time.