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1.
C Julien C Barres P Kandza J Sassard 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1989,308(8):219-222
Intra-aortic blood pressure (BP) was measured in conscious rats after early chronic destruction of the peripheral sympathetic nervous system (SNS) with guanethidine. In sympathectomized rats, the mean level of BP was not different from that of control rats but its variability was markedly increased. These results indicate that functional integrity of the SNS is of primary importance for the short-term control of BP but is not essential for its long-term maintenance. 相似文献
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GABAA-receptors, the major synaptic targets for the neutotransmitter GABA, are gated chloride channels. By their allosteric drug-induced modulation they serve as molecular control elements through which the levels of anxiety, vigilance, muscle tension and epileptiform activity can be regulated. Despite their functional prominence, the structural requirements of fully functional GABAA-receptors are still elusive. Expression of cDNAs coding for the 1- and 1-subunits of rat brain yielded GABA-gated chloride channels which were modulated by barbiturates but displayed only agonistic responses to ligands of the benzodiazepine receptor. GABAA-receptors with fully functional benzodiazepine receptor sites were formed when the 1- and 1-subunits were coexpressed with the 2-subunit of rat brain. These receptors, however, failed to show cooperativity of GABA in gating the channel. In order to determine the subunit repertoire available for receptor assembly in different neuronal populations in vivo, the sites of subunit gene expression were (1, 2, 3, 5, 6, 1, 2, 3, 2) mapped by in situ hybridization histochemistry in brain sections. The mRNAs of the 1-, 1- and 2-subunits were co-localized e.g. in mitral cells of olfactory bulb, pyramidal cells of hippocampus as well as granule cells of dentate gyrus and cerebellum. The lack of colocalization in various other brain areas points to an extensive receptor heterogeneity. The presence of multiple GABAA-receptors in brain may contribute to synaptic plasticity, differential responsiveness of neurons to GABA and to variations in drug profiles.Special issue dedicated to Dr. Erminio Costa 相似文献
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A new fluorescent acridine orange derivative, 3-amino-6-methoxy-9-(2-hydroxyethylamino) acridine (AMHA), has been applied to Hela cells in order to set up appropriate conditions for the detection of mycoplasma contaminations. Since AMHA staining reveals intensely fluorescent nuclei and slight fluorescent cytoplasm, we can visualize and localize mycoplasma contamination on each cell. In combination with a shortened Chen's staining method (1977), AMHA should allow a better detection of mycoplasma in animal cell cultures than the well established Hoechst dye. 相似文献
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K99 lectin fromEscherichia coli was purified and biotinylated via its carboxyl groups using biocytin hydrazide and a water soluble carbodiimide. Biotinylation of two out of the nine carboxyl groups was sufficient to permit detection of the lectin by avidin and did not cause any loss of the haemagglutinating activity. It was demonstrated that the biotinylated K99 lectin retained other important properties of native K99 and that it will probably become a very sensitive detecting reagent. Indeed, it was able to bind to HeLa cells, as do intact bacteria carrying K99 fimbriae, and also to recognizeN-glycolyl-neuraminyl-lactosyl-ceramide in an overlay binding assay.
Abbreviations: NeuAc,N-acetylneuraminic acid; NeuGc,N-glycolylneuraminic acid; PBS, phosphate buffered saline (0.9% NaCl containing 150mm sodium phosphate, pH 7.2); LPS, lipopolysaccharide; BCHZ, biocytin hydrazide; EDC, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide; BSA, bovine serum albumin; SDS-PAGE, sodium dodecyl sulfate-polyacrylamide gel electrophoresis; DMEM, Dulbecco's modified Eagle medium. For the gangliosides, trivial names and structures are given according to the recommendations in [43]. NeuAc2-3Gal1-4Glc1-1Cer (NeuAc-GM3); NeuGc2-3Gal1-4Glc1-1Cer (NeuGc-GM3); GalNAc1-4(NeuAc2-3)Gal1-4Glc1-1Cer (GM2); NeuAc2-8NeuAc2-3Gal1-4Glc1-1Cer (GD3); Gal1-3GalNAc1-4(NeuAc2-3)Gal1-4Glc1-1Cer (GM1); NeuAc2-3Gal1-3GalNAc1-4(NeuAc2-3)Gal1-4Glc1-1Cer (GD1a); Gal1-3GalNAc1-4(NeuAc2-8NeuAc2-3)Gal1-4Gle1-1Cer (GD1b); NeuAc2-3Gal1-3GalNAc1-4(NeuAc2-8NeuAc2-3) Gal1.-4Glc1-1Cer (GT1b). NeuGc2-3Gal1-4GleNAc1-4Gal1-4Glc1-1Cer (NeuGc-SPG). 相似文献
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Sabine Lhernould Yannis Karamanos Sylvain Bourgerie Gerard Strecker Raymond Julien Henri Morvan 《Glycoconjugate journal》1992,9(4):191-197
We have previously isolated mannoside and xylomannoside oligosaccharides with one or two terminal reducingN-acetylglucosamine residues from the extracellular medium of white campion (Silene alba) suspension culture. We have now demonstrated the presence of peptide-N
4-(N-acetylglucosaminyl)asparagine amidase (PNGase) activity in cell extracts as well in the culture medium that could explain the production of those compounds. An additional xylomannoside, (GlcNAc)Man3(Xyl)GlcNAc(Fuc)GlcNAc, was characterized, and1H- and13C-NMR assignments for the oligosaccharide Man3(Xyl)GlcNAc(Fuc)GlcNAc were obtained using homonuclear and heteronuclear spectroscopy (COSY).Abbreviations Endo
endo--N-acetylglucosaminidase
- Fuc
fucose
- GlcNAc
N-acetylglucosamine
- Man
mannose
- NMR
nuclear magnetic resonance
- PNGase
peptide-N
4-(N-acetylglucosaminyl)asparagine amidase
- Xyl
xylose 相似文献