[Regulation of intracellular cholesterol synthesis in hypercholesterolemia by glucocorticoids].

The rate of endogenous cholesterol synthesis in blood lymphocytes and skin fibroblasts from patients with type IIa hyperlipidemia was found to be increased in comparison with healthy donors. The cells of hyperlipidemic patients had lowered levels of glucocorticoid receptors concomitantly with a partial loss of their sensitivity to glucocorticoids. In fibroblasts from patients with hereditary hypercholesteremia of homozygous type the number of glucocorticoid receptors did not exceed 10% of their content in normal cells.

[Role of sex hormones in the development of atherogenic dyslipoproteinemia in boys of pubertal age].

Interrelationships of hypercholesterolemia (HCS), hypertriglyceridemia (HTG) or hypo-alpha-cholesterolemia (hypo-CS HDL) and the blood levels of sex hormones were investigated in boys aged 14-15 to detect variations in the levels of sex hormones to define groups of adolescents at the highest risk of developing atherogenic dyslipoproteinemia (DLP). A conclusion has been made that HCS and hypo-CS HDL development is associated with changes in the blood levels of testosterone and estradiol, and a low blood level of T in HTG is of secondary origin with regard to the development of this type of DLP.

[Endocrine status changes in children with bronchial asthma].

A study was made of adrenocortical function by measuring blood plasma cortisol concentration and amount of glucocorticoid receptors in lymphocytes as well as thyroid function by measuring blood plasma triidothyronine and thyroxine concentration in 58 bronchial asthma children aged 1 to 14 years. The authors revealed alterations in the functional activity of the indicated endocrine glands depending on the intensity of bronchial patency disorders and the nature of the therapeutic measures carried out.

[Effects of recent alcohol intake on high density lipoprotein accepting properties and their interactions with liver cells].

HDL-subfraction was studied in blood serum of drinkers after alcohol intake and control group of men-nondrinkers. Blood serum incubation with fibroblasts culture did not indicate principal differences between drinkers and nondrinkers both with normolipemia and hyperalphacholesterolemia. Increase of HDL2 and decrease of HDL3-subfraction were observed.

[Changes in high density lipoprotein subfractions during interaction with fibroblasts and hepatoma G-2 in various dyslipidemias].

Subfractional alterations of high density lipoproteins (HDL) were studied after incubation of blood serum from patients with normal lipid spectrum and with four types of dyslipidemia (hypercholesterolemia, hypertriglyceridemia, hypo- and hyper-alpha-cholesterolemia) in mixtures containing human skin fibroblasts and G-2 hepatoma cells used as typical populations of peripheric and liver cells. Incubation of normolipidemic blood sera with fibroblasts overloaded with cholesterol led to conversion of small HDL3 particles into large HDL2 subfractions arising due to the lipoprotein acception of cholesterol. At the same time, incubation of these blood sera with the hepatoma cells resulted in a decrease of the large particles ratio in total pool of HDL because of their absorption by the cells.

[Reduced cell sensitivity to glucocorticoid hormones in hypercholesterolemia].

The number of 3H-dexamethasone binding sites in lymphocytes of subjects with hypercholesterolemia (HCS) was found to be decreased as compared to the receptor level in normolipidemic patients (N). In HCS-lymphocytes, the dexamethasone-induced inhibition of 3H-thymidine and 14C-acetate incorporation was less pronounced (by 20% and 22%, respectively) than in control cells, which is suggestive of the decreased sensitivity of HCS-lymphocytes to the hormone. An addition of 5-25% HCS blood sera to human skin fibroblast cultures caused a 10-50% decrease in the number of 3H-dexamethasone binding sites and diminished the Kd values 2-3 times.

[Subfractionated conversions of high density lipoproteins in vitro in sera with various lipid spectra].

Using gradient gel electrophoresis, the interconversions of high density lipoproteins (HDL) upon heating for 24 hours at 37 degrees C of blood sera obtained from dyslipidemic patients, were studied. It was shown that during incubation of normolipidemic, hypercholesterolemic and hyperalphacholesterolemic sera, the portion of large particles of HDL2 subclass (HDL2b) is increased with a simultaneous decrease in the portion of the smallest particles of HDL3 subclass (HDL3b and HDL3c). Contrariwise, in hypertriglyceridemic and hypoalphacholesterolemic sera the portion of the largest HDL2b particles is decreased, while that of middle-sized HDL3a is increased.

[The use of ammonium sulfate for the preparation of control sera with elevated levels of cholesterol, triglycerides and high density lipoprotein cholesterol].

Fractionation of human blood serum, using ammonium sulfate and dextran sulfate, enabled to obtain fractions containing lipoproteins of low and high density as well as lipoproteins of very low density including low density lipoproteins. The fractions obtained could be used for special enrichment of native blood serum with known classes of lipoproteins in order to produce blood serum containing high amount of cholesterol, triglycerides and high density lipoprotein cholesterol, respectively, required for control evaluation of lipid assays.

[Mechanism of activating the lymphocyte glucocorticoid receptor in acute myocardial infarct].

Dose-dependent increase in content of highly specific binding sites for glucocorticoids (receptors), but without alteration in their affinity to the hormone, was observed after incubation during 2 hrs of healthy donor lymphocytes with blood serum of patients with acute myocardial infarction. The similar effects exhibited protein extracts of necrotized and normal parts of human myocardium (heart antigens) as well as the autologous blood serum and human blood serum albumin treated with UV-irradiation. Number of receptors was not altered in human skin fibroblasts incubated both with the patients blood serum and with the UV-treated blood serum.

[Hypoalphacholesterolemia: dynamics of the subfractional spectrum of high density lipoproteins during their interaction with fibroblasts and hepatoma Hep-G2 cell line].

Using gradient gel electrophoresis, the dynamics of subfractional spectrum of high density lipoproteins (HDL) according to the particle size was studied during HDL interaction with hepatoma Hep-G2 cells and human skin fibroblasts. It was found that incubation of sera obtained from normolipidemic donors with cholesterol-loaded fibroblasts results in a decrease of the proportion of all small-sized particles of the HDL3 subclass, i.e.

[Isolation of fractions of human serum suitable for selective alterations in the level of lipids and apolipoproteins during preparation of standard sera].

A procedure is developed for isolation of human blood serum fractions, enriched with lipoproteins of definite classes and meant for production of standard human blood sera. Addition of one of these fractions to native human blood serum enabled to increase distinctly selectively the content of main components of corresponding lipoproteins. Lipoprotein-free blood serum might be used as a diluent for a decrease in concentration of lipoproteins and their components in the initial blood serum, while content of the other components was maintained.

[Sex hormones in dyslipoproteinemias and disorders of arterial blood pressure in boys 11-12 years of age].

A survey of boys with hypercholesterolemia, hypertriglyceridemia, hypo-alpha-cholesterolemia, a combination of hypo-alpha-cholesterolemia and hypertriglyceridemia, and hyperalphacholesterolemia, and control subjects from two Moscow districts demonstrated significantly elevated plasma testosterone and estradiol values in boys with hypo-alphacholesterolemia. Increased estradiol was also found in boys with hypercholesterolemia and hyperalphacholesterolemia. An inverse relationship between plasma testosterone level and high density lipoprotein (HDLP) cholesterol, and a direct relationship between the estradiol/testosterone ratio and HDLP cholesterol were established.

[Insulin and C-peptide secretion after physical exertion in men with newly manifested stenocardia and chronic ischemic heart disease].

Variation in insulin and C peptide levels was examined in patients with angina of new onset and chronic coronary heart disease. Insulin secretion was increased in all coronary patients, as compared to the controls, and hormonal response to additional stress was abnormal in postmyocardial infarction patients. It is demonstrated that insulin secretion is already changed at early stages of coronary disease, and the pattern of change is presented.

[The amount of thrombocyte alpha 2-adrenoreceptors in patients with different clinical variants in the course of ischemic heart disease].

Number of alpha-2-adrenoceptors on the thrombocyte membranes was measured with selective antagonists [H]3 yohimbine in 25 patients with ischemic heart disease (7 patients with unstable 12 with vasospastic and 6 with new onset angina pectoris) and in 16 patients without ischemic heart disease and coronary atherosclerosis (control group). The number of alpha-2-adrenoceptors in patients with unstable angina pectoris (571.0 +/- 92.

[Effect of prostaglandins I2 and E1 on the cholesterol level in cultured smooth muscle cells from the human aorta].

Prostaglandins I2(PGI2) and E1(PGE1) (5 X 10(-7) M) reduced by 30% the content of intracellular cholesterol in cultured human aorta smooth muscle cells after 24 hrs of incubation in a medium without fetal calf serum. Total HDL, as well as HDL3 and HDL2b fractions stimulated the effect of prostaglandins on the reduction (by 50%) of cholesterol level.

[Lipoprotein-dependent synthesis of prostacyclin in smooth muscle cells].

Low (LDL) and high density lipoproteins (HDL) stimulated prostacycline (PGI2) synthesis in rabbit and human aorta smooth muscle cells growing in culture. The lipoproteins were added to the cells in concentrations equal to that of cholesterol. It was shown that HDL exerted a stronger stimulating effect as compared to LDL.

[Reconstruction of highly purified proton-translocating pyrophosphatase from Rhodospirillum rubrum].

Using the freezing-thawing procedure, a highly purified preparation of PPase from R. rubrum chromatophore membranes was incorporated into soybean phospholipid liposomes. The activity of reconstituted PPase was increased in the presence of the uncoupler, FCCP, and the antibiotics, valinomycin (+KCl) and nigericin (+KCl).

[Effects of lipids on the activity of soluble mitochondrial pyrophosphatase and its conversion to the membrane-bound form].

The effects of lipids on the activity of soluble and membrane-bound pyrophosphatase from beef heart mitochondria were studied. An addition of total mitochondrial lipid, phosphatidyl choline, phosphatidyl ethanolamine or cardiolipin resulted in stimulation of the enzymatic activity and an increase in thermal stability of the soluble enzyme. The maximal activating effect was exerted by the total mitochondrial lipid and phosphatidyl choline.

[Inhibitory analysis as an approach to investigation of regulation of ATP and pyrophosphate biosynthesis in mitochondria].

The effect of respiration rate on the content and accumulation of ATP and PPi in rat liver mitochondria was studied. It was found that the syntheses of ATP and PPi occur at different respiration rates. It was assumed that the respiration rate can determined the formation of ATP or PPi via oxidative phosphorylation.

[Isolation and primary characterization of two forms of inorganic pyrophosphatase from ox heart muscle mitochondria].

A method allowing to obtain two highly purified forms (membrane-bound and soluble ones) of inorganic pyrophosphatase from bovine heart mitochondria is described. Both forms have the isoelectric point of 5.8, pH optimum with Mg2+ at 7--9, are maximally stable at pH 5.