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461.
The metabolic parameters and functional state of hypothalamic systems in mice with the Yellow mutation in the Agouti locus and with obesity of the melanocortin type and the effect of metformin (MF) treatment (9 days, 200 mg/kg/day) were studied. The MF treatment led to decreased body weight and to normalization of glucose tolerance in mice. In the hypothalamus, MF restored the decreased activity of Akt kinase, the main component of leptin pathway, and normalized the increased expression of subtype 1B serotonin receptor. The obtained data suggest the efficiency of MF to treat obesity of the melanocortin type.  相似文献   
462.

Background  

Macrophage migration inhibitory factor (MIF) has special pro-inflammatory roles, affecting the functions of macrophages and lymphocytes and counter-regulating the effects of glucocorticoids on the immune response. The conspicuous expression of MIF during human implantation and early embryonic development also suggests this factor acts in reproductive functions. The overall goal of this study was to evaluate Mif expression by trophoblast and embryo placental cells during mouse pregnancy.  相似文献   
463.
The genomes of various Brucella species were shown to contain hypervariable sequences which can be detected by the M13 DNA. It has been demonstrated that the method of DNA fingerprinting opens up new possibilities in differentiation and identification of Brucellosis agents.  相似文献   
464.
465.
The esterase action of thrombin and trypsin on N-arylsulfonyl-valyl-arginine methyl esters was studied. The values of Km and kcat under steady-state conditions at pH 8,5 were determined. It was shown that the nature of the arylsulfonyl group does not affect the kinetic parameters of the reactions under study. The Michaelis constants of the thrombin-catalyzed reactions appeared to be one order of magnitude lower than the Km values of the corresponding TAME analogs.  相似文献   
466.
The influence of frontal cortex extirpation on the amount of monoamines in the brain structures was investigated in chronic experiments on rats trained according to the method of motor feeding reflexes with bilateral reinforcement. Monoamine levels were measured by high performance liquid chromatography with electrochemical detection. By the ninth day after the ablation serotonin (5-HT) and dopamine (DA) levels were significantly reduced in the cortex and the striatum, respectively, while noradrenaline ++ (NA), 5-HT, dihydroxyphenylacetic and 5-hydroxyindoleacetic acid levels in raphe nuclei and locus coeruleus were increased. The level of conditioned reflex reproduction was 39% on the light and 33% on the sound stimulus. The involvement of monoamines in the recovery of conditioned reflexes after frontal cortex extirpation is discussed.  相似文献   
467.
The effect of ionized air containing negatively charged ions at a concentration of 320000–350000 ions/cm3 inhaled by rats was studied. It was demonstrated that the inhalation of negative air ions for 60 min activated the secretion of goblet cells without impairing the tracheal mucosa and changing the protein profile of bronchoalveolar lavage. It was also found that the level of spontaneous production of reactive oxygen species by unfractionated blood cells increased after the action of negative air ions in both males and females. However, the intensity of their generation induced by opsonized zymosan increased only in females. Different sensitivities of the female and male blood antioxidant enzymes—superoxide dismutase and glutathione reductase—to negative air ions were observed. These results allow the effect of negative air ions on the respiratory organs and blood to be interpreted as priming and weak activation via a direct action on the mucosa of primary target respiratory organs and then on the blood.  相似文献   
468.
Russian Journal of Plant Physiology - Mutant strains of the filamentous cyanobacterium Anabaena strain PCC 7120 ΔHup (dc-Q193S and dc-R284H) with amino acid substitutions located in the...  相似文献   
469.
Repeated exposure to amphetamine (AMPH) induces long‐lasting behavioral changes, referred to as sensitization, that are accompanied by various neuroadaptations in the brain. To investigate the chemical changes that occur during behavioral sensitization, we applied a comparative proteomics approach to screen for neuropeptide changes in a rodent model of AMPH‐induced sensitization. By measuring peptide profiles with matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry and comparing signal intensities using principal component analysis and variance statistics, subsets of peptides are found with significant differences in the dorsal striatum, nucleus accumbens, and medial prefrontal cortex of AMPH‐sensitized male Sprague–Dawley rats. These biomarker peptides, identified in follow‐up analyses using liquid chromatography and tandem mass spectrometry, suggest that behavioral sensitization to AMPH is associated with complex chemical adaptations that regulate energy/metabolism, neurotransmission, apoptosis, neuroprotection, and neuritogenesis, as well as cytoskeleton integrity and neuronal morphology. Our data contribute to a growing number of reports showing that in addition to the mesolimbic dopamine system, which is the best known signaling pathway involved with reinforcing the effect of psychostimulants, concomitant chemical changes in other pathways and in neuronal organization may play a part in the overall effect of chronic AMPH exposure on behavior.  相似文献   
470.
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