[Animal experiment studies of chronic thiamine deficiency. Changes in carbohydrate and amino acid metabolism under resting and load conditions].

The metabolic effects of thiamine deficiency on the metabolism of lactate, acid-base and amino acids were evaluated both with and without muscular exercise in a controlled animal experiment. Thiamine deficiency - in good correlation with its biologic halftime and also with reports in the literature - caused with a latency of 17-56 days and statistically proven in parallel the following effects: hyperlactemia; in comparison to controls elevated plasma concentrations of threonine, alanine, glutamic acid, glutamine, histidine, methionine, taurine, valine, isoleucine and leucine; distinctly lowered - also in comparison to controls - plasma concentrations of arginine and tryptophan. Furthermore, in the thiamine deficient rats predetermined muscular exercise caused the following effects, also occurring concomitantly: life threatening lactacidosis; marked - statistically prover - disturbance of the homeostasis of alanine, glycine, methionine and arginine; distinctly - and statistically significant - elevated plasma concentration of proline; statistically significantly lowered plasma concentrations of taurine. The reasons for all these changes under thiamine deficiency is most likely a metabolic one primarily due to a disturbance of the utilization of pyruvate in the liver. An additional disturbance of both the transsulfuration pathway and the Krebs-Henseleit-cycle seems probable. The physiologic regulation of pyruvate, lactate, alanine, serine and tyrosine during muscular exercise in correlation to the controls is being discussed.