[The effect of prenatal hyper- and hypoglycemia on liver mitochondrial function and carbohydrate metabolism in rat pups]. / Vliianie prenatal'noi giper- i gipoglikemii na funktsiiu mitokhondrii pecheni i uglevodnyi obmen u krysiat.

Hypoglycemia at the initial stage of the prenatal development decreased the level of glucose in the rat blood, increased glucose-6-phosphatase in the liver. Hyperglycemia increase the glucose content in the blood with relatively minor changes of the glucose-6-phosphatase activity and oxidation of hydrocarbonates.

[Effect of hyperglycemia and hyperthermia on liver mitochondrial respiration and blood glucose content of rats during postnatal ontogenesis]. / Vliianie giperglikemii i gipertermii na dykhanie mitochondrii soderzhanie gliukozy v krovi krys v postnatal'nom ontogeneze.

Correlation between glucose level in blood and liver mitochondrial energetics of 1, 10, 20-days rats under hyperglycemia and high environmental temperature (38 degrees C) has been studied. Glucose feeding led to a significant increase of glucose content in blood, this increase being less at hyperthermia. Glucose feeding strengthened the oxidation of such intermediates as succinate (Krebs cycle), pyruvate and malate (hydrocarbonates) and caprylate (lipid). High environmental temperature with hyperglycemia suppresses the liver mitochondria breathing, hydrocarbon and lipid intermediates being used; the suppression is less in the presence of succinate. It is found that liver mitochondria of growing rats at different experimental conditions oxidize different intermediates with various rates. These data can be explained in the light of ontogenetic evolution of the energetic apparatus. It is supposed that exogenic glucose is the factor which activates growing processes of animals and to certain extent diminishes the negative influence of hyperthermia on the organism.

[The reaction of a pregnant female and of her just-born rat pups to a change in ambient temperature and in the blood glucose level]. / Reaktsiia beremennoi samki i rodivshikhsia krysiat na izmenenie vneshnei temperatury i urovnia gliukozy v krovi.

Cold exercises and hyperglycemia were found to exert a benevolent effect on the reproductive function and postnatal development of rats. Warmth and hyperglycemia during early periods of pregnancy led to a disturbance in the reproductive function and postnatal development in rats.

[The effect of carbohydrate metabolic changes during pregnancy on the capacity of liver mitochondria in rat progeny to oxidize the lipid intermediate]. / Vliianie izmenenii uglevodnogo obmena vo vremia beremennosti na sposobnost' mitokhondrii pecheni potomstva krys okisliat' lipidnyi intermediat.

Respiration rate, respiration control and ADP of liver mitochondria were studies in one-, ten-, and twenty-day-old rats born of females who had received subcutaneous insulin injections (0.25 U/100 g body weight) on days 5-7, 11-13 and 19-21 of pregnancy or glucose (1 g/100 g body weight, in the morning before feeding). Caprylate, an intermediate of the lipid metabolism, was used as the substrate for oxidation. In the control, caprylate oxidation in one-day old rats occurred at a low rate without providing for synthesis of ATP from ADP and phosphate. Insulin administration and alimentary hyperglycemia in females on days 5-7 of pregnancy had no significant effect on respiration rate of liver mitochondria in progeny of all ages tested. Administration of the above preparations on days 11-13 and 19-21 of pregnancy improved caprylate oxidation in mitochondria of the newborn rats. In other series the difference between experiments and the control was insignificant. Metabolic changes in the newborns are shown to be related to hyperinsulinemia in pregnant females.

[The characteristics of lactate oxidation in the tissue mitochondria of rats of different ages]. / Osobennosti okisleniia laktata v mitokhondriiakh tkanei krys raznogo vozrasta.

The parameters of respiration (V3, V4) and phosphorylation (the respiration control, ADP/O) have been studied using lactate as a substrate (obligatory with NAD addition) close by meaning to pyruvate on the liver and heart mitochondrion and homogenates of newborn rats. In 20-days and adult rats the mitochondria and homogenates oxidize the lactate (with NAD) with higher rate V4 but with lower value of respiration control as compared with the newborn animals. Simultaneously, a high activity of mitochondrial NADH-oxidase, oxidizing NADH, formed in the reaction of lactate dehydrogenase not connected with ATP synthesis. The role of mitochondrial NADH-oxidase are discussed as a factor increasing lactate oxidation, removing tissue lactate and activating the age dependent energy metabolism.

[The respiratory activity of the liver mitochondria and the viability of rat pups subjected to changes in their carbohydrate metabolism in the prenatal development period]. / Dykhatel'naia aktivnost' mitokhondrii pecheni i zhiznesposobnost' krysiat, podvergnutykh izmeneniiami ikh uglevodnogo obmena v prenatal'nyi period razvitiia.

It is shown that hyperglycemia after insulin introduction to the pregnant rats delays oxidation of pyruvate and malate by liver mitochondria as well as decreases offspring vitality. Digestive hyperglycemia activates utilization of this intermediate by liver mitochondria, that increases the rat vitality.

[The oxidation of different substrates by liver mitochondria from rat pups in early postnatal development]. / Okislenie raznykh substratov mitokhondriiami pecheni krysiat v rannem postnatal'nom razvitii.

We have studied the respiratory ratio of liver mitochondria during oxidation of substrates of the carbohydrate and lipid metabolism in newborn rats and during early postnatal development. High rate of respiration coupled with the synthesis of ATP from ADP and phosphate has been found during oxidation of carbohydrate substrates (pyruvate + malate); however, caprilate, a substrate of lipid metabolism, does not support such respiration. However, in the young rats aging from 2 to 30 days utilization of carbohydrate and lipid substrates via the phosphorylating pathway proceeds with similar efficacy.

[Oxidation of lactate in isolated rat heart mitochondria]. / Okislenie laktata v izolirovannykh mitokhondriiakh serdtsa krysy.

In unwashed mitochondria the oxidation of L-lactate (with NAD+) proceeds in presence of the added lactate dehydrogenase. The respiration is characterized by the high rate in state 4 and is stimulated by ADP. This process takes place in unwashed mitochondria and homogenate of the heart in absence of added lactate dehydrogenase. Oxidation of lactate with NAD+ is inhibited by rotenone. It has been also revealed that the oxidation of glutamate is insufficiently altered in presence of lactate (with NAD+) in unwashed mitochondria as compared with the washed ones. It is supposed that the stimulating effect of lactate with NAD+ on the mitochondria respiration is not so much a result of the membrane-damaged action as a result of oxidation of lactate dehydrogenase reaction products: phosphorylative oxidation of pyruvate and nonconjugated oxidation of NADH. Utilization of these products takes place in the main respiratory chain, including its first stage.

[Characteristics of the oxidation of the intermediates of carbohydrate and fat metabolism in the liver mitochondria of young rabbits during perinatal development]. / Osobennosti okisleniia intermediatov uglevodnogo i zhirovogo obmena v mitokhondriakh pecheni krol'chat v period perinatal'nogo razvitiia.

Respiratory activity of liver mitochondria has been studied in perinatal rabbits (29 day old embryos, neonatal and 30 day old rabbits). Intermediates of carbohydrate metabolism, pyruvate (with malate), as well as of fat metabolism, caprylate, were used as oxidative substrates for mitochondria. Pyruvate was shown to be oxidized more intensively, particularly in liver mitochondria of newborn rabbits. Mitochondrial enzyme system is supposed to promote the oxidation of carbohydrate substrates which is characteristic of a given tissue during perinatal development.

[Respiration of mitochondria from brown fat and the mechanism of thermogenesis]. / Dykhanie mitokhondrii buroi zhirovoi tkani i mekhanizm termogeneza.

It is shown that both phosphorylating and nonphosphorylating (noncoupled) respirations, the latter being regulated by GDP and increasing in a series of substrates - pyruvate + malate----succinate----NADH----ascorbate(+ cytochrome c) have been presented in brown fat mitochondria of newborn guinea pigs and of adult rats under thermoneutral conditions. Noncoupled respiration is suggested to support thermogenesis not only under cold exposure but under thermoneutral conditions as well.

[Effect of cold exposure on energy processes in the tissues and on the growth of rats in the early postnatal period]. / Vliianie kholodovogo vozdeistviia na énergeticheskie protsessy v tkaniakh i rost krys v pannii postnatal'nyi period.

The effect of different temperature conditions on postnatal development of rats has been investigated. Considerable deviations in growth rate, vitality of rats and tissue energetic processes during the intensive cold action (5-6 degrees C) have been revealed. Under such conditions the local increase of nest temperature up to 30 degrees C causes the growth stimulation, increase of vitality and optimization of energetic processes in liver and heart. The dependence of the studied indices on the degree of the thermoregulatory system formation is under discussion.

[Effect of thyroidectomy and subsequent L-thyroxine administration on the content of various lipids in the organs of rats of different age]. / Vliianie tireoidektomii i posleduiushchego vvedeniia L-tiroksina na soderzhanie nekotorykh lipidov v organakh zhivotnykh raznogo vozrasta.

Total lipid, phospholipid and cholesterol content in the tissues of the liver, myocardium, skeletal muscle, intestine and the blood plasma was studied on three groups of rats (control, thyroidectomized, and thyroidectomized to which l-thyroxin was administered); the animals were aged 2, 6 months and 2 years. All the indices studied increased in the tissues and the blood of intact animals with the advance of age at different percentage ratio. As to thyroidectomized animals, cholesterol and phospholipid content increased in all the organs under study at the age of 2 and 6 months, and fell in the old ones. Total lipid content rose at the age of two months and decreased in the sexually mature and old rats. In the thyroidectomized animals to which l-thyroxin was administered cholesterol and total lipid content rose in all the tissues, excluding the blood plasma, whereas phospholipid content reduced in all the organs under study.

[Growth and heat resistance of rats repeatedly exposed to heat during early ontogenesis]. / Rost i teplovaia ustoichivost' krys, podvernutykh v rannem ontogeneze povtornym teplovym vozdeistviiem.

The influence of a 10-fold heat training from the 1st to the 10th to the 20th, and from the 20th to the 30th days after birth on further growth and resistance of the animals to the high temperature was investigated. The growth and survival of rats was found to depend on the regimen of heat training. The animals aged 10 to 20 days proved to be most sensitive to the action of high temperature. Heat resistance of these rats turned out to be maximally increased at the period of primary sexual maturation, and the growth rate was retarded in comparison with the animals subjected to heat training at other age periods.

[Effect of thermal load and ACTH administration on the ATPase activity of homogenates and microsomal fractions of the tissues of growing rats]. / Vliianie teplovoí nagruzki i vvedenie ACTH na ATF-aznui u aktivnost' gomogenatov i mikrosomal'nykh fraktsii tkanei radtushchikh krys.

A study was made of the age dynamics of the ATP-ase activity in the homogenates and the microsomal fractions of the liver, kidneys, brain and muscles of albino rats. It was shown that in young animals the change of the ATP-ase activity in the tissues (the index of energy metabolism) in response to the ACTH administal life the shifts in the ATP-ase activity of different tissues after the thermal stress and administration of ACTH proved to vary in character.