[Changes in the transaldolase activity in the liver, spleen and bone marrow of rats after total X-ray irradiation]. / Izmenenie aktvnosti transal'dolazy v pecheni, selezenke i kostnom mozge krys posle total'nogo rentgenovskogo oblucheniia.

The paper deals with changes in the activity of transaldolase in tissues of the liver, spleen and bone marrow of rats 4.24 h and on the 3 d, 7th, 18th, 30th, 45th, and 60th day after total X-ray irradiation in a dose of 600 R. The ionizing irradiation causes a stable inhibition of the enzyme activity in All tissues. The observed changes are homogeneous in their direction but have their own peculiarities for each tissue. Differences in the degree and extent of the enzyme activity changes at various stages of the X-ray lesion development in the tissues under study may be explained by their different sensitivity to the penetrating radiation.

[Peculiarities of reaction activity of the pentose phosphate pathway in different tissues]. / Osobennosti aktivnosti reaktsii pentozofosfatnogo puti v razlichnykh tkaniakh.

The paper deals with the most important pentose phosphate pathway reactions of carbohydrate metabolism in tissues of the liver, spleen, bone marrow and in blood erythrocytes catalyzed by transketolase. Possibilities are also studied for pentose phosphate production in the mentioned tissues in the nonoxidized reaction of the pentose phosphate pathway catalyzed by transketolase. It is established that due to this reaction the possibility of pentose phosphates synthesis in tissues of the liver, spleen, bone marrow and erythrocytes is very small as compared with that in the oxidative reactions of the pentose phosphate pathway. The reaction rate is higher in the reverse direction when utilizing erytrhroso-4-phosphate and riboso-5-phosphate with glycolysis intermediate products formed. It is also shown that erythroso-4-phosphate inhibits greatly the glucose phosphate isomerase activity. Coming from the data obtained the authors suggest that acceleration of the transketolase reaction towards the utilization of erythroso-4-phosphate as well as of synthesis of fructoso-6-phosphate and glyceraldehyde-3-phosphate promotes the transfer of carbohydrate metabolism from the pentose phosphate pathway to glycolysis.