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The physiological (10(-8)M) concentration of free thyroxine (T4) and specific thyroxine-binding protein (a thyroxine action modulator-MDT4) was studied for its effect on protein synthesis, respiration and oxidative phosphorylation of mitochondria in the liver and brain of developing rats. Free T4 was demonstrated to affect the studied parameters in the mitochondria of the liver and brain of the developing rats very rarely, if at all. In the liver MDT4 stimulated mitochondrial functional activity during all the studied developmental periods whereas in the brain mitochondria the modulator stimulated the synthesis of proteins and phosphorylating respiration only in early postnatal life. In the following periods of development there was a modulator-induced decrease in protein incorporation of labelled leucine, respiration, and conjugation strength of brain mitochondria. The findings suggest that thyroidal hormones ambiguously regulate the functional status of mitochondria in the liver and brain of the developing rats and the specific hormone-binding protein MDT4 takes an active part in this regulation.

The effect of thyroid hormones and the methylation inhibitor 5-azacytidine on the level of expression of thyroid hormone-responsive genes (malic enzyme and 6-phosphogluconate dehydrogenase genes) has been studied. DNA-RNA hybridization has shown there is an inverse correlation between the level of DNA methylation and gene expression of malic enzyme and 6-phosphogluconate dehydrogenase. Thus it suggests that the regulation of thyroid hormone gene expression can take place via DNA methylation blocking and that DNA demethylation is part of structural changes essential to the binding of thyroid hormones with DNA elements recognized by thyroid hormone receptors and to further induction of synthesis of specific mRNA.

Analysis of blood flowing from the rat thyroid has shown that an acute immobilization stress enhanced thyroid hormone secretion with an increase of the T3/T4 x 100 index. The most marked response to stress was observed after repeated 2 min immobilization with a 3 min interval. Such increase of secretion was arrested by injection of prazosin, an alpha-adrenoblocker. Propylthiouracil injected an hour before the experiment reduced T4 thyroid conversion index. These results permit a conclusion that short-term repeated immobilization enhanced thyroid hormone secretion via alpha-adrenergic system stimulation, this being paralleled by increased production of hormonally more active T3.

The effect of physiological, concentration of thyroxine and cytoplasm thyroxine-binding protein (thyroxine action modulator, TAM4) on the RNA-polymerase activity in rat liver and bain cells in ontogenesis was studied. The physiological doses of the hormone were shown not to effect the RNA-polymerase of isolated liver and brain nuclei, while TAM4 caused the stimulation of enzymatic activity in these organs. ++TAM4 stimulating effect in liver correlated with increasing animal age, while the maximum RNA-polymerase activation by tAM was discovered in young rats under one month-At later stage the RNA-polymerase activity was same as in the controls. In is suggested that the cytoplasmic hormone-binding proteins take part in the formation of liver and brain sensitivity to the action of the thyroid gland hormones.

By collecting in situ the blood flowing from the thyroid, the authors have demonstrated that noradrenaline injected in a dose 1 microgram/kg into rabbit thyroid artery enhanced triiodothyronine secretion without changing thyroxin secretion. This process was inhibited by prazosin, an alpha-adrenoblocker, in a dose 1 microgram/kg, injected 5 min before noradrenaline, but not by propranolol, a beta-adrenoblocker. Phenylephrine, an alpha-adrenergic agonist, in a dose 1 microgram/kg, injected into the thyroid artery, influenced thyroid hormone secretion similarly as noradrenaline. The T3/T4.100 ratio taken as an indicator of T4 thyroid conversion increased under the effect of noradrenaline injection after prazosin. Thus, in our experiment noradrenaline activated thyroid function via stimulation of alpha-adrenoceptor system. Hence, catecholamines are capable of directly influencing thyroid functional activity.

The role of thyroxin and thyroxin action modulator (cytoplasmic protein mediating some hormonal effects on the mitochondria and nucleus) in rat liver and brain protein phosphorylation was studied in experiments. In the liver, an organ sensitive to thyroid hormones, the modulator was found to stimulate the activity of specific protein kinases contributing to protein phosphorylation, and co-incubation of physiologic concentrations of T4 with the modulator enhanced the stimulatory effect. In the brain change of the thyroid status did not change the protein kinase activation. Incubation of T4 and thyroxin effect modulator did not change the enzymic activity either.

A single external gamma-irradiation (1 Gy) of rats on day 35 of their life causes stable structural and functional disturbances in the thyroid gland leading to the development of hypothyrosis at the remote times following irradiation which is demonstrated by the decrease in the concentration of thyroxine in the blood, increase in the thyrotropic function of the hypophysis and inhibition of the activity of tyrosine-dependent enzyme, alpha-glycerophosphate dehydrogenase, in the liver. Disturbances induced by such exposure in the thyroid gland of adult rats are insignificant and compensatory in time.

The levels of glycosylated hemoglobin (HbA1c) and glycosylated keratin were studied along the hair length in 17 patients with newly detected insulin dependent diabetes mellitus (IDDM) aged 7 to 33, in 14 patients with newly detected noninsulin dependent diabetes mellitus (NIDDM) aged 46 to 73, and in 41 healthy subjects. The level of glycosylated keratin in healthy hairs along the entire length varied within 0.094-0.124 mumol of fructosamine per 100 mg of hair. In 10 of 17 patients of the IDDM group measurements of glycosylated keratin levels made it possible to determine the time of appearance of diabetes mellitus, in 13 patients of the NIDDM group these levels along the entire hair length were elevated. The determination of these levels permitted the estimation of the time of appearance of IDDM. Its manifestation followed a long period (1-2 yrs.) of latent derangements of carbohydrate metabolism. In NIDDM patients the time of appearance of disease is difficult to determine because of the limited hair length and a long latent period of disease (over 2-3 yrs.).

Experiments were made on 100 random bred rats of various age groups, controls and animals exposed to single external gamma-radiation at a dose of 1 Gy on the 35th day of life. Thyroxine and triiodothyronine concentrations were investigated in peripheral blood and separately in arterial blood, in thyroid, portal and hepatic venous blood. The activity of T4 conversion into T3 by 5'-deiodinating enzymes of the liver microsomal fractions and the activity of the liver mitochondrial enzymes--cytochrome of C-oxidase and alpha-glycerophosphate dehydrogenase were also investigated. A decrease in thyroid excretion of T4 and T3 and T4 blood concentration was noted in rats exposed to irradiation. 5'-thyroxine deiodinating activity of the microsomal enzymes was elevated in the liver of such rats; a T3 ratio in the blood outflowing from the liver was on the increase. A conclusion has been made that 5'-deiodination in the liver of rats with postradiation hypothyrosis is effected as a result of increased production of the most active hormone T3 from less active T4.

Rat liver and kidney microsomal fractions contain 5'-deiodinase, converting thyroxin into 3,5,3'-triiodothyronine. In control animals a marked decrease in thyroxin concentration takes place when the blood passes through the liver and kidney (triiodothyronine level being preserved). Fasting causes a prominent decrease in blood thyroxin, a small decrease in triiodothyronine as well as a drop of glucose and insulin levels. At the same time a decrease in thyroxin deiodinase activity takes place in the liver; as for the kidney a decrease is less marked. Fasting rats have no gradients in the blood passing through the liver and kidney; triiodothyronine balance remains unchanged. The results show that the rat liver and kidney deiodinase activity regulation (during changes in the body physiological status) helps to maintain triiodothyronine optimum concentration in general circulation.

Comparative and competitive analyses of thyroxine (T4) and triiodothyronine (T3) binding to highly purified rat liver, brain and lung cell plasma membranes were carried out. The dependence of hormone binding on the time, temperature and concentration was studied. The effects of trypsin and partial delipidation on the binding parameters of thyroid hormones were investigated. Two thyroid hormone-binding sites were detected in cell plasma membranes of all tissues under study. The maximal binding of T4 to rat liver membranes and the maximal binding of T3 to rat brain membranes was observed in all experiments, the affinity for T3 being higher than that for T4. An important role of both protein and lipid components of plasma membranes in the membrane reception of thyroid hormones is proposed.

The purpose of the paper is to define the role of low molecular weight cytoplasmic proteins of peptide nature in the synthesis of young rat liver and brain mitochondrial proteins. The cytoplasmic modulator isolated from the hyperthyroid rat liver was shown to stimulate the synthesis of mitochondrial proteins of the hyperthyroid rat liver. A similar modulator from the hyperthyroid rat brain did not affect the protein-synthesizing apparatus of thyroidectomized rat liver mitochondria. In a cell-free system, containing brain mitochondria of rats with a different thyroid status, the cytoplasmic modulator failed to influence the incorporation of labeled amino acids in mitochondrial proteins. It is assumed that cytoplasmic low molecular weight modulators participate in a differentiated response of different organs to the action of thyroid hormones.

A highly purified thyroglobulin mRNA was isolated from human nodal euthyroid goiter. A full-length cDNA was synthesized from 33S RNA by using reverse transcriptase in the presence of human placenta ribonuclease inhibitor. A DNA complementary to human Tg mRNA was used in liquid hybridization experiments to quantify Tg mRNA. The amount of Tg mRNA in euthyroid nodal and congenital goiter was reduced. In thyroid cancer Tg specific mRNA was absent. Direct correlation between Tg gene expression in thyroid cells and DNAase-I hypersensitivity of chromatin from the thyroid gland nucleus was revealed.

The injection of 0.5 mM of adrenalin and 3.3 X 10(-3) M of propranolol in the thyroid artery of the thyroid lobe perfused in a thermostatic chamber (37 degrees C) 1h after the beginning of perfusion caused a decrease in the index of thyroid deiodination by 48 and 37%, respectively. Adrenalin injection 2 h after TSH lowered the stimulating effect of the latter on thyroxine thyroid conversion. A conclusion is made that adrenalin testing can suppress the activity of thyroid conversion of T4 into T3 and decrease the activity of TSH-stimulated deiodination.

Studies have been made on the effect of high temperature and intensive insolation upon the uptake of iodide and hormone formation in the thyroid of rodents (Rhombomys opimus, Spermophilopsis leptodactylus, Citellus fulvus) with different adaptation to the environment. It was shown that high temperature in combination with solar radiation significantly decreases functional activity of the thyroid and affects some of the physiological indices of the organism. Animals with different ecological specialization differ in their reaction to factors of the hot climate.

A study was made of the role played by specific iodinethyrodine-binding proteins of rat hepatocytes in the process of nucleo-cytoplasmic interrelations of the thyroid hormones under normal conditions in thyroidectomy and in experimental thyrotoxicosis. The concentration of the hormone-binding sites in the cell depended on the thyroid hormone level outside the cell. An important role of the cytosol hormone-binding proteins in the accumulation and interacellular distribution of the thyroid cell hormones is emphasized. The absence of any participation of cytosol triiodine-thyronine binding proteins in the process ofpenetration of the hormone into the nucleus was revealed. Triiodine-thyronine level in the nuclei depended directly on the concentration of the recptor proteins in them and the degree of occupation of the acceptor sites in the receptors proper.

Effects were studied of various doses of thyroid hormones and thyroidectomy on oxidation of palmityl carnitine and caprylate in heart and liver mitochondria as well as on the rate of oxidation of succinate and alpha-ketoglutarate in brain mitochondria. Depending on the dose of the thyroid hormone the rate of fatty acid oxidation varied. The stimulatory doses of thyroxin and thyroidectomy altered (increased or decreased) the rate of electrone transport in the respiratory chain but the respiratory control and the ADP/O ratio were only slightly changed. Toxic doses led to fast oxidation of the both substrates and to uncoupling of the oxidative phosphorylation. Thyroid hormones and thyroidectomy did not affect the succinate oxidation in brain mitochondria; this data suggest insensitivity of the brain tissue to the effect of thyroid hormones.

The content and distribution of iodoamino acids in thyroglobulin of the cryopreserved thyrotoxically-changed thyroid parenchyma were studied, as was thyroglobulin iodination. Thyroid tissue obtained during operations of patients with diffuse-toxic goiter was investigated. The thyroid parenchyma was cryopreserved according to the method developed at the Institute of Cryobiology and Cryomedicine Problems, Academy of Sciences of the Ukrainian SSR. The tissues were stored for 4-6 months. Thyroglobulin was isolated by gel filtration of the thyroid saline extract through a column packed with Sephadex G-200. Thyroglobulin was iodinated with KI + I2 water solution, pH 9.2, at 37 C for 30 min. The amount of iodine added was 100 moles of I2 per protein mole. Protein concentration was determined by the biuret reaction. Thyroglobulin iodoamino acid composition was determined by direct spectrophotometry. Absorption spectra were measured by an EPS-3T recording spectrophotometer ("Hitachi", Japan). The processes of freezing (-196 degrees C) and thawing of the thyroid parenchyma were shown to induce no changes in the thyroglobulin iodoamino acid composition. Cryopreservation of the thyroid parenchyma considerably affected iodine incorporation and formation of iodoamino acids in the thyroglobulin during its in vitro iodination. It may be supposed that cryopreservation of the thyroid tissue affects the thyroglobulin conformational status, that results in increased iodination of this iodoprotein.

Cytoplasmatic glycoprotein previously shown to be an inhibitor of mitochondrial membrane permeability for oxidation substrates inhibits in-vitro gluconeogenesis from pyruvate, lactate, succinate, alpha-ketoglutarate and glutamate in slices of the renal cortical layer. The inhibition was reduced with Ca2+ concentration increase in the incubation medium from 0.02 to 2 mM.

It was shown that cAMP increased the capacity of polyribosomes of the thyroid glands to the labeled phenylalanine incorporation into the protein by 51 per cent. Preincubation of microsomes or ribosomes with cAMP in the cell-free protein-synthesizing system also increased the incorporation of the labeled amino acids into the protein by 54 and 49 per cent, respectively. The optimal effect occurred with the concentration of cAMP of 0.2 mg/ml. cAMP in a concentration of 0.8 mg/ml inhibited the incorporation of the labeled amino acids by 32 per cent. This can possibly be attributed to the forming products of cAMP degradation. Modification of the protein-synthesizing system (ATP--1 mM. GTP--1.6 mM) led to the fact of an increase in the level of the labeled amino acid incorporation into the protein by 54 per cent; the simulating effect of cAMP persisted. In the absence of ATP in the incubation medium addition of cAMP failed to stimulate the protein synthesis. Thus, cAMP stimulated protein synthesis in the thyroid gland in vitro, with utilization of ribonucleoproteid particles.

This is an experimental work. Investigations were carried out on albino rats on the 18th day of pregnancy. A study was made of I-131-labelled thyroxin penetration from the maternal organism into the fetus and vice versa. Radiological and radiochromatographic analysis of the blood samples of both the mother and the fetuses at various time intervals after the administration of radioactive thyroxin showed that the isotope in the form of thyroxin failed to penetrate from the mother to the fetus and vice versa. A conclusion was drawn that during prenatal development the function of the fetal thyroid gland was automatic.

Analysis of proteins, synthesized in cell-free system using nodal euthyroid goiter, was carried out by polyacrylamide gel disc electrophoresis. Four protein farctions, incorporating labelled amino acids, were found: "complete" thyroglobulin, two its subunits and thyroalmbumin. This correlates with the concept that malignant cell synthesizes intensively proteins untypical for a normal tissue.

Incubation of rat liver mitochondria with 3H-and 14C-cAMP under the conditions which are conducive to the activation of mitochondrial respiration by cAMP resulted in the penetration of cAMP into the mitochondria. Subfractionation of mitochondria was made with the use of digitonin and 0.1% Triton X-100. cAMP was incorporated into all the fractions investigated. A close correlation (r = +0.97) between 3H- and 14C-labelling of the mitochondria and submitochondrial fractions was found thus showing that the label was not only diluted but also accumulated by the mitochondria.

Cytoplasmatic glycopeptide-induced bicarbonate ion electrogenic transport through mitochondrial membrane has been studied. Glycopeptide, described earlier as a factor increasing inner mitochondrial membrane permeability for phosphate ions, has been also shown to induce bicarbonate ion electrogenic transport through inner mitochondrial membrane. HCO3- ion transport, induced by cytoplasm glycopeptide is realized by pH-dependent pore. The interrelation of cytoplasm glycopeptide with mitochondria is regulated by mitochondrial energization.

The phospholipid spectrum and their content in the liver, heart, kidneys and the brain of rats was studied comparatively under normal conditions and in alloxan diabetes. Under pathological conditions there occurred significant changes in the amount of individual phospholipids in all the organs, but the most pronounced changes were noted in the brain. A sharp increase of cardiolipin content and a regular reduction of choline-containing lipids--lecithin and sphyngomyelin--in the organs under study were characteristic of alloxan diabetes. Oscillations in the concentration of other phospholipid fractions (phosphatidyl serine, phosphatidylinositol, phosphatidylethanolamine) had a definite organic specificity.

Upon starving and muscle work the activity of an insulin-dependent cytoplasmic regulator (IDR) in the rat liver has been demonstrated to be lowered. This is one of the mechanisms of glycogenolysis and gluconeogenesis stimulation. Rapid increase in IDR activity in the heart and liver has been recorded in the period of recovery after swimming, with the increase being more intense in the heart. It has been shown that in the heart the resynthesis of glycogen proceeds more rapidly than in the liver. Therefore, the rate of glycogen resynthesis by the liver and heart correlates with IDR activity.

The manifestation of Ca2+/2H+ antiporter activity in rat liver mitochondria was shown to be inhibited in thyroidectomy and stimulated in hyperthyroidosis. Experiments with measuring the kinetics of the swelling of deenergized mitochondria in isoosmotic solutions Ca (NO3)2, pH 8.1 demonstrated inhibition of the swelling of liver mitochondria during thyroidectomy and stimulation because of administering thyroid hormones in vivo. During thyroidectomy, the phosphate-induced swelling of rat liver mitochondria was powerfully inhibited. Meanwhile administration of thyroxine to rats stimulated the swelling of mitochondria.

The ratio of membrane-bound and free polyribosomes in thyroid gland cells was decreased two-fold in nodular euthyroid goiter and five-fold--in Hashimoto thyroiditis; a slight increase in thyroglobulin synthesis in free polyribosomes was noted in goiter. Impairments in transfer of the translation products across membranes of rough endoplasmic reticulum may be one of the causes of deteriorations in thyroglobulin synthesis in goiters.

A study was made of cyclic guanosine-3+, 5+-monophosphate (cGMP) on protein synthesis in the cell-free system of the thyroid gland. Preincubation of S30 fraction with cGMP led to increase of labeled amino acid incorporation into proteins (by 56% with the cGMP concentration of 1.73 X 10(-5) M, and by 160% with the concentration of 2 X 10(-4)). No stimulating effect was observed on addition of cGMP directly into the incubation medium. The results obtained suggested that protein synthesis was stimulated under the effect of cGMP at the translation level. The same protein fractions [27S, 19S, 12S, 3-8S (I) and 3-8S (II)] were revealed by disc-electrophoresis of soluble proteins synthesized in the cell-free system in which polyribosomes preincubated with cAMP (1.73 X 10(-5) M) were used as in the system devoid of cAMP. Specific radioactivity of thyroglobulin subunits corresponded in experiments with cAMP to that in experiments without cAMP. At the same time specific radioactivity of 19S thyroglobulin was more than doubled. It can be supposed that thyroglobulin subunit synthesis was accelerated under the effect of cAMP, and, as a result, labeled thyroglobulin increased in the system. The data obtained confirmed a hypothesis put forward earlier that cAMP had a direct influence upon the translation process.

The efficacy of a prolonged (an average of 24.2 days) subcutaneous insulin administration using a Soviet apparatus NDL (a portable drug dosing apparatus) of paracorporal type was studied in 30 patients with type I diabetes mellitus. As a result of therapy a stable compensation of carbohydrate metabolism was achieved in 26 patients, subcompensation in 4 patients; glycemia circadian variations and requirements in insulin in most cases decreased. Simultaneously a clinical improvement of the patients' general status was observed. The use of a prolonged subcutaneous administration of insulin using the NDL was recommended for patients with insulin-dependent diabetes mellitus with a grave form, a labile course and insulin resistance that was difficult to control.

Iodotyrosine and iodothyronine residues are formed in the protein molecule during bovine thyroglobulin iodination in vitro. Dissociation and reassociation of the thyroglobulin molecule have no significant influence on its iodoaminoacid composition. Thyroglobulin iodination in the presence of 8 M urea does not result in thyroxine synthesis despite the increased formation of iodotyrosine residues. Similarly, during iodination of reassociated thyroglobulin the new molecules of thyroxine are not formed either. It is presumed that during reassociation of thyroglobulin subunits the native conformation of the protein is not completely reconstituted. The results obtained suggest that the structure of thyroglobulin controls the distribution of the iodine atoms incorporated by the iodoaminoacid residues.

Activity of cytoplasmic inhibitor of Ca2+ transport in rat heart mitochondria was studied after total ischemia and incubation of heart homogenates with cAMP. Distinct inactivation of the inhibitor occurred under these conditions. The decrease of the inhibitor activity in ischemic myocardium appears to serve as a compensatory mechanism: 1. pyruvate dehydrogenase and the enzymes of tricarboxylic acid cycle were activated due to increase in Ca2+ concentration in mitochondria, 2. as a result of Ca2+ accumulation in mitochondria the elevated concentration of Ca2+ was decreased in myoplasm, which developed after impairment of plasmatic membranes and of sarcoplasmic reticulum membranes.

Development of rabbit fetal tissues sensitivity to thyroxin was studied on the basis of changes in alpha-glycerophosphate oxidase activity in the liver mitochondria of pregnant rabbits and their fetuses to which thyroxin was administered at different stages of pregnancy. T4 administration up to the 23rd day of gestation caused an increase in the enzyme activity in the maternal liver mitochondria only, whereas in the fetus it was at the control level. From the 24th day of pregnancy an increase of the alpha-glycerophosphate oxidase activity was seen in the fetal liver mitochondria. This can be explained by the appearance of rabbit fetal tissues sensitivity to maternal thyroxin at this period of gestation, increasing by the end of pregnancy.

Chronic contamination of rats with heliotrin causing the development of hepatitis or hepatocirrhosis and partial hepatectomy to decrease the amount of liver cellular elements resulted in intolerance to glucose, a decrease in the sensitivity of the body to insulin, hyperinsulinemia after a glucose-tolerance test. The content of glycogen in the liver of the heliotrin contaminated rats was much lower than that in the controls and after glucose-tolerance an absolute increment of glycogen in the controls was 8.8-fold higher than in the heliotrin-contaminated rats. It was concluded that a decrease in glucose-tolerance and hyperinsulinemia in patients with chronic hepatitis and hepatocirrhosis were determined by a decrease in the amount of functionally active liver cellular elements and the development of insulin resistance.