[Characteristics of thiamine diphosphate metabolism in the liver in acute hypobaric hypoxia].

Rates of thiamin diphosphate accumulation in rat liver tissue and its subsequent depletion were decreased within the first hour after vitamin B1 administration into the animals with oxygen insufficiency. Hypoxia apparently inhibited simultaneously the processes of thiamin diphosphate biosynthesis and degradation, as a result of which content of the coenzyme was unaltered in tissues under conditions of usual intake of thiamin. The data obtained suggest that the activity of enzymes, participating in thiamin diphosphate turnover and estimated in vitro do not reflect their real functioning in the whole organism. Importance of ATP, ADP and pyridine nucleotides is considered as regulating agents of enzymes participating in thiamin diphosphate turnover under hypoxia.