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A I Marzoev

Publications and source records attributed to A I Marzoev.

29 records · Page 2Linked to original sources
PubMedDate not supplied

[The role of thyroid hormones in the regulation of electric stability of erythrocyte membranes in rats].

A method of electric breakdown was used for a study of electric stability (durability) of the membranes of erythrocytes isolated from the blood of normal rats and rats with hypo-, hyperthyrosis and thyrotoxicosis. Erythrocytic membrane electric durability was shown to depend on the hormonal status. In particular, an increase in the potential of breakdown of erythrocytes of hyperthyroid rats was shown in comparison with the characteristics of erythrocytes of the other studied populations. Judging by the test thyrotoxicosis was accompanied by a decrease in a degree of physical homogeneity of erythrocytic membranes. There were no differences in electric durability between erythrocytes of normal and hyperthyroid animals.

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[Effect of thyroid hormones on the physico-chemical properties of lipids in the liver mitochondria of rats].

The administration of thyroxine to rats (300 micrograms per 100 g of body mass intraperitoneally) resulted in a decrease in the content of cardiolipin, cholesterol and an increase in lysophosphatidylethanolamine in rat mitochondria as compared to normal in 48 hours. During the registration of spin-labeled mitochondrial lipids using the EPR method thyroid-related changes in the regulation parameter on Arrenius' charts were detected suggesting the regulation of the physical state of mitochondrial lipids by thyroid hormones. It was assumed that the observed hormone-related modifications of the physicochemical state of mitochondrial lipids illustrated the membranotropic mechanism of the regulation of mitochondrial functions by thyroid hormones.

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[Effect of thyroid hormones on heat-induced changes in the EPR-spectra of erythrocytes].

An increase in the fluidity of membranes in experimental hyperthyreosis of rats was shown by the registration of EPR-signals labeled with spin probe (5-dosilsterate). Modifications of the physical state of erythrocytic membranes induced in vivo by thyroid hormones were shown to depend on the fatty acid composition of food fats. Thus, the simulation of hyperthyreosis against a background of a diet with more viscous fats (pork lard) was accompanied by a decrease in the fluidity of erythrocytic membranes, whereas food enrichment with polyunsaturated fats (sunflower oil) inhibited the effect of hyperthyreosis on the structural state of membranes. An increase in the fluidity of membranes also resulted from the incubation of erythrocytes of normal animals with physiological concentrations of triiodothyronine (10(-9) M). Under these conditions adding up of thyroxine (10(-7) M) prevented the effect of the first hormone on the structure of membranes. It was assumed that a modifying effect of thyroid hormones in vivo was partially based on rearrangements in the fatty acid composition of membrane lipids.

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[Characteristics of the levels of various nucleic acid precursors in the tissues of rabbits with various thyroid conditions].

The content of the precursors and metabolites of nucleic acids in the brain and liver of normal rabbits, rabbits with hypothyrosis (thyroidectomy) and hyperthyrosis (100-150 Mg of L-thyroxine per 1 kg of body mass daily for 10-12 days) was determined by liquid chromatography with a high resolution. A decrease in the content of deoxyguanosine, thymine, hypoxanthine, cytosine, thymidine and an increase in the content of inosine, adenine and adenosine in the liver of animals with hypothyrosis were shown. In the brain of these rabbits the level of cytidine was lowered, and the levels of deoxyguanosine, thymine, inosine, hypoxanthine, adenine and uracil were on an increase. An increase in the levels of deoxyguanosine, thymine, adenine, thymidine and a decrease in the levels of cytidine, hypoxanthine, cytosine, adenine and uracil in the liver were noted in hyperthyrosis. In the brain of rabbits with hyperthyrosis an increase in the levels of deoxyguanosine, cytidine, inosine and adenine was combined with a decrease in the levels of thymine and hypoxanthine. These thyroid-dependent changes in the content of registered metabolites and precursors of nucleic acids in tissues suggest that the observed shifts illustrate one of many mechanisms of the regulation of cell metabolism by thyroid hormones.

Adenine↗
PubMedDate not supplied

[Peroxidation of blood serum lipids in rabbits with various thyroid functions].

Chemiluminescent properties of blood serum from rabbits with hypo-, normo- and hyperthyroidism were investigated. The ferrum-induced chemiluminescence of the serum was shown to be decreased both in hypo- and in hyperthyroidism as compared with the normal state. The oxidative capacity of the main substrate of the peroxidation in blood serum--apo-B containing lipoproteins--did not markedly differ in various states of thyroid gland. The efficiency of branched free radical chains was dissimilar; these data suggest that the content of lipid-soluble antioxidants was increased in the lipoproteins in hypo- and decreased in hyperthyroidism. Measuring of the chemiluminescence quenching in the standard chemiluminescent system indicated that the content of water-soluble antioxidants was increased in blood of animals both with hypo- and hyperthyroidism. However, a higher content of water-soluble antioxidants was noted in blood of rabbits with hypothyroidism as compared with the animals with hyperthyroidism.

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[Thyroid hormones and the level of divalent iron ions in the rabbit liver].

Experimental hypothyreosis in animals was obtained by means of extirpation of thyroid gland; hyperthyreosis was obtained by thyroxine injections intraperitoneally for 10 days. Content of Fe2+ ions of the free pool (not bound with ferritine) was estimated with the ESR method, after treatment with sodium nitrite. A decrease in Fe2+ ions content is observed in liver homogenate of hypothyroid rabbits, and an increase is observed in that of the hyperthyroid animals. Content of Fe2+ ions in cells of liver tissues correlates with the oxidation capacity of the mitochondrial lipids. The changes in the rate of lipid peroxidation under thyroid pathology is supposed to result from changes in free ferrum content.

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[Thyroid hormones and EPR signals of the liver, brain and blood].

Experimental hypothyreosis was caused by thyroidectomy, hyperthyreosis developed after intraperitoneal administration of thyroxine into animals within 10 days. In liver and brain preparations amplitudes of EPR signals were decreased with g = 2.00 and g = 1.94, respectively, in hypothyreosis and were increased in hyperthyreosis. The ratio of these signals amplitudes was unaltered in brain tissue but in liver tissue it varied depending on thyroid status. In liver tissue intensity of other signals was increased in hyperthyreosis ad decreased in hypothyreosis, except for the signal with g = 2.25 (cytochrome P = 450) the intensity of which decreased in hyperthyreosis and increased in hypothyreosis. These phenomena appear to be relevant to various disorders of metabolism in pathologies of thyroid glands.

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[Role of hyperthyroidism and the fatty component of the diet in changes in the fatty acid composition of the liver mitochondrial lipids in rats].

The influence of hyperthyrosis and the diet fat component on the hepatic mitochondrial fatty-acidic content was studied in Wistar rats. The animals, divided into two groups, were kept within 20 days on synthetic diets enriched with proteins (18%), carbohydrates (56%), fats (26%), vitamin and salt mixtures. The first group of animals was given the butter diet ("B" group) and the second one received the sunflower-seed oil ration ("S" group). It was found that after three weeks from the beginning of the diet the content of hepatic mitochondrial fatty acids was changed according to the fatty-acidic spectrum of alimentary fats. However, the fatty acid unsaturation indices, i.e. the unsaturated fatty acid % X unsaturated bond number, were not different in both mitochondrial populations studied. Hyperthyrosis (induced by 50 micrograms of thyroxin/100 g body weight within 5 successive days intraperitoneally), simulated in the presence of the above diets, not only intensified changes, caused by the diet in the mitochondrial fatty acid content, but induced further variance in the fatty-acidic spectra, being distinctly seen in the "B" group animals. In particular, hyperthyrosis in these animals was accompanied by a fall of linoleic (25%) and arachidonic (36%) acids in the mitochondrial lipid content, being the main cause of decreasing the mitochondrial lipid unsaturation indices by 26%. The alteration of lipid parameters in mitochondria of hyperthyroid animals of the "S" group was less pronounced, being 6%, 11% and 9%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

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[Determination of phospholipase A2 activity in liver mitochondria using fluorescent dye 1,8-anilinonaphthalene sulfonate].

Quantitative estimation of free fatty acids was carried out in liver mitochondria of normal and thyroidectomized rabbits by means of two procedures--spectrophotometry using rhodamine 6Zh and a fluorescent method with 1,8-aniline naphthalene sulfonate /ANS/ as a dye. The use of ANS enabled to estimate quantitatively the free fatty acids beginning from 25 nmol in a sample /with eggor of about 17%/ by visual evaluation of the spot areas. As compared with the rhodamine procedure, use of ANS permitted to increase 5-fold the sensitivity of free fatty acid estimation, to elevate 6-fold the accuracy of the analysis, to overcome the step of fatty acid elution from chromatogramms and to decrease the time required for analysis. The data obtained suggest that the hyperthyroid state in rabbits was accompanied by an increase in the phospholipase A2 activity in liver mitochondria.

Anilino Naphthalenesulfonates↗