The ontogenetic correlations of noradrenaline level and adrenergic receptor density in the rat brain

We studied the level of noradrenaline and the density of alpha 2- and beta-adrenoreceptors in the brain stem and cerebral cortex of 12-day- and 21-day-old rat fetuses, as well as of rats at the ages of 1, 2, 5, 7, 9, 16, 21, 35, and 70 days. We found a positive correlation between the level of noradrenaline in the brain stem and the density of beta-receptors in the cerebral cortex, and between the amount of alpha 2- and beta receptors in the cerebral cortex, as well as between the values of each of these indices of the neurochemical system and body weight. Significant negative correlations (r = -0.72 and r = -0.88, respectively) were found between the amount of alpha 2-adreno-receptors in the brain stem and the content of noradrenaline in this brain region, as well as in the cerebral cortex. Explanations of these positive and negative correlations between the level of noradrenaline and the amount of adrenergic receptors in the rat brain during ontogenesis are discussed.     

The phospholipid composition of the liver in root voles living under different radioecological conditions

The effect of the increased natural radiation background (within some areas in Komi Republic) and man-caused radioactive contamination in the Chernobyl NPP accident zone on the composition of liver phospholipids in Microtus oeconomus inhabiting these areas was studied. The significant changes in the liver lipid composition in rodents inhabiting both the Chernobyl accident zone and the areas with the increased natural radiation background were found. The maximal changes in the liver phospholipid composition were revealed during the first year after the accident. The reverse dependence between the phosphatidyl choline/phosphatidyl ethanolamine ratio and the ratio between the sum of more readily oxidizable phospholipids and the sum of more poorly oxidizable ones was found. However, the slope of corresponding curves significantly depends on the radioactive state in the area of the population inhabitance. The conclusion about high sensitivity of the lipid composition of hepatocytes in Microtus oeconomus both to the impact of the man-caused radioactive contamination and the increased level of the natural radioactivity was drawn.     

Effects of fluoxetine and its complexes with glycyrrizhinic acid on behavior and brain monoamine levels in rats

Effects of serotonin uptake inhibitor fluoxetine (F) and it's complexes with glycyrrizhinic acid (GA) in molar proportions 1GA : 1F (FGA-1) and 4GA : 1F (FGA-4) on rat behavior in elevated plus-maze and brain monoamine concentrations were studied. Drugs (25 mg/kg) were administered per os 1 h before investigations. F-treated rats showed increased anxiety and reduced locomotor activity, whereas FGA-1 and FGA-4 had no effects on the behaviors. None of the compounds modified brain tissue serotonin content, but all of them decreased the level of its metabolite 5-hydroxyindole-3-acetic acid level in the hypothalamus, and FGA-4 also decreased it in the cortex. Noradrenaline levels were increased in the hypothalamus of rats treated with F in both combinations with GA. In the striatum, F increased dopamine and its metabolite DOPAC levels, but their ratio (an indicator of the neurotransmitter turnover) was not altered by this drug. Unlike F, FGA-1 significantly activated dopamine turnover in the striatum. The data obtained suggested that application of F in complexes with GA significantly modified the drug behavioral effects and these alterations may be related to specific effects of the pure compound and its complexes on the functions of the brain monoaminergic systems that regulate investigated behavior.     

A synthesis of heteroaromatic S- and N-beta-glycosides of N-acetylglucosamine under phase transfer conditions

The use of crown ethers for a phase transfer-catalyzed synthesis of heteroaromatic glycosides of N-acetylglucosamine was studied. The solid-liquid system and the catalysis by 15-crown-5 were found to provide for both a 100% conversion of the alpha-D-glucosaminyl chloride peracetate and a high reaction rate. The interaction of alpha-D-glucosaminyl chloride peracetate and oxadiazole and triazole mercapto derivatives capable of thiol-thione tautomerism carried out at room temperature in acetonitrile in the presence of anhydrous potassium carbonate and crown ethers was shown to lead to both S- and N-glycosides. The structures of the compounds synthesized were confirmed by X-ray analysis and 13C and 1H NMR spectroscopy.     

The parameters of antioxidant status of tissues in the offspring of tundra vole (Microtus oeconomus Pall.) inhabiting areas with increased natural radioactivity

The parameters of the lipid peroxidation regulatory system (the antioxidative and antiperoxidant activities, the peroxide content, the lipid peroxidation intensity) in the tissues and the activities of the antioxidative defence enzymes (the peroxidase activity in blood, the superoxide dismutase activity in the blood erythrocytes) are studied in progeny of tundra vole which are reproduced from parent inhabiting areas with different radioecological environment during a long time. The progeny had the preservation of the changed antioxidant status. The scale of the changing of the investigating parameters depend on the state of radionucleoids contamination of areas where tundra voles are caught, sex of rodents, the content of antioxidants in lipids of tissues of parents.     

Assessment of 90Sr concentration in dental tissue using thin-layer beta-particle detectors and verification with numerical calculations

Electron paramagnetic resonance (EPR) measurements of tooth enamel can be used as an individual biological dosimeter for external dose assessment. However, the presence of 90Sr in the tooth tissues makes the task of interpreting EPR tooth dosimetry more complicated. The determination of the dose contribution of incorporated 90Sr in calcified tissue to the total dose measured by EPR is one of the main aspects of correct interpretation of EPR tooth dosimetry. In this work, experimental and numerical calculations were performed to convert the measured beta-particle dose rate to 90Sr concentration in calcified tissue. The cumulative beta-particle dose was measured by exposing artificially contaminated dentin and enamel to thin-layer alpha-Al2O3:C detectors in two different exposure geometries. Numerical calculations were performed for experimental exposure conditions using calculations of electron transport and secondary photons [Monte Carlo n-Particle Transport code version 4C2 (MCNP)]. Numerical calculations were performed to optimize the sample size and exposure geometry. The applicability of two different exposure conditions to be used in routine analysis was tested. Comparison of the computational and experimental results demonstrated very good agreement.     

Catalyzed asymmetric dialkylzinc addition to benzaldehyde in the presence of new chiral ligands--delta-(1-phenethyl)aminoalcohols

A series of delta-aminoalcohols prepared from (S)- and (R)-N,N-dimethyl-1-phenethylamines was found to catalyze the enantioselective addition of diethylzinc to benzaldehyde to yield optically active 1-phenylpropanol with enantiomeric excess 60-85%.     

Ontogenetic correlations between noradrenaline level and the density of adrenergic receptors in the rat brain

We studied the level of noradrenaline and the density of α2-and β-adrenoreceptors in the brain stem and cerebral cortex of 12-day- and 21-day-old rat fetuses, as well as of rats at the ages of 1, 2, 5, 7, 9, 16, 21, 35, and 70 days. We found a positive correlation between the level of noradrenaline in the brain stem and the density of β-receptors in the cerebral cortex, and between the amount of α2- and β-receptors in the cerebral cortex, as well as between the values of each of these indices of the neurochemical system and body weight. Significant negative correlations (r=−0.72 andr=−0.88, respectively) were found between the amount of α2-adrenoreceptors in the brain stem and the content of noradrenaline in this brain region, as well as in the cerebral cortex. Explanations of these positive and negative correlations between the level of noradrenaline and the amount of adrenergic receptors in the rat brain during ontogenesis are discussed.