[Effects of chronic radiation exposure on erythrocyte metabolism and functioning].

The structural and functional state of blood erythrocytes in people exposed to radiation during Chernobyl NPP accident was studied two or six years later. The changes in oxygen transport system of erythrocytes and in the ratio between some organic phosphate fractions were observed. The beta-carotene per os administration to rats during low-level irradiation increased hemolytic stability and activity of glycolytic enzymes, that bears witness to the increasing of organism adaptive reactions at provitamin administration during irradiation.

[Correcting effect of nicotinamide on hemoglobin glycosylation in streptozotocin diabetes in rats].

Streptozotocin induced diabetes in rats was accompanied by development of hyperglycemia, by increase in the rate of hemoglobin and albumin glycosylation in blood and by elevation of 2,3-diphosphoglycerate content in erythrocytes. Alterations of the dissociation properties and the decrease in Hb P50 value suggested the reduced affinity of hemoglobin to oxygen. Injection of nicotinamide, which is involved in NAD+ biosynthesis, caused a decrease of glucose content in blood, stabilized the content of 2,3-diphosphoglycerate and of glycosylated hemoglobin in erythrocytes.

[Nicotinamide coenzymes in the regulation of cellular metabolism in various types of diabetes].

Hypoglycemic and hypolipidemic effects of nicotinamide in insulin-dependent and noninsulin-dependent types of diabetes have been investigated. Hypoglycemic effect of nicotinamide in alloxan- and streptozotocin-induced diabetes resulted in activation of NAD+ biosynthesis and corresponding alterations in the redox state of free nicotinamide coenzymes. Increase in the free NAD+/NADH ratio was accompanied by inhibition of key gluconeogenic enzymes and by a decrease in the rate of 2-14C-incorporation into glucose in liver tissue and by inhibition of sorbitol formation in lens tissue.

[Inhibition of the transport of citrate during ADP-ribosylation of inner membrane proteins of the mitochondria].

The ability of rat liver submitochondrial particles to catalyze NAD+ hydrolysis with a transfer of ADP-ribose residues to protein membranes has been demonstrated ADP-ribosylation is directly dependent on NAD+ concentration upon saturation with 1 mM NAD+ and is inhibited by physiological compounds (e.g., ATP, 10 mM; nicotinamide, 10 mM); besides, it is an artificial acceptor of ADP-ribose, arginine methyl ester.

[Citrate transport in submitochondrial particles of the rat liver].

The submitochondrial particles (SMP, inverted inner membrane vesicles of mitochondria of the turned out vesicles in internal mitochondrial membranes) of the rat liver are characterized for their ability to incorporate [14C]citrate depending on the concentration of exogenic citrate, temperature and time of incubation. The rate of citrate incorporation into SMP does not depend on the addition of the oxidation substrate into the medium, however in the presence of malate and phosphate it is sharply activated. 1,2,3-benzene tricarboxylase (1,2,3-BTC) is an active inhibitor of the citrate transport into SMP.