[The transketolase activity in erythrocytes as a criterion for thiamine balance in the body].

In deficiency of thiamin the transketolase activity was decreased in patients and in experimental animals. The data obtained showed the high sensitivity of transketolase from erythrocytes to hypovitaminosis B1. At the same time, in diseases, especially accompained by hypoxia (and also by avitaminosis B1), the transketolase activity was shown to be increased. The effect was observed in relation to an increase in amount of young erythrocytes, which contained more transketolase. In these cases it was reasonable to estimate not only the transketolase activity but also other characteristics of thiamin metabolism (content of the vitamin in food, urine and blood).