[Characteristics of intracellular metabolism of carbohydrates and amino acids in animals with thiamine deficiency].

Vitamin B1 deficiency in mongrel albino rats induced by oxythiamine is concomitant with an increase in the ratio of free forms of NAD+/NADH, NADP+/NADPH in liver mitochondria. This is accompanied with a rise in steady-state concentrations of isocitrate, 2-oxoglutarate and with a decrease of malate in liver tissue, which testifies to the prominent regulatory role of the 2-oxoglutarate dehydrogenase complex in the intracellular metabolism under vitamin B1 deficiency. Moderate physical load causes a 10-fold increase in the steady-state concentration of pyruvate and lactate in the blood of thiamine-deficient animals, which seems to be due to the stimulation of glycolysis in the maintenance of energy homeostasis. The observed increase in the excretion of pyruvate, lactate, 2-oxoglutarate (30-fold against control) and pentose phosphates (3-fold) with urine, depending on the degree of vitamin B1 deficiency, points to one of essential mechanisms of cell metabolism stabilization under the given pathological condition.