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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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Isabelle Matricon 《Cell and tissue research》1973,136(4):569-578
Résumé L'épithélium pharyngien d'Alcyonidium polyoum possède des cellules pourvues d'une très grande vacuole. L'incompressibilité du liquide vacuolaire permet un élargissement brusque de l'organe lors de la contraction du manchon musculaire strié qui enserre cette vacuole. Les fibres musculaires sont insérées sur le plasmalemme apical par des filaments unitifs. Le point d'attache est relié à la lame amorphe du cell-coat qui entoure les microvillosités par des fibrilles, réalisant probablement une liaison mécamique plus efficace. Le reticulum sarcoplasmique porte des ribosomes. Le cytoplasme apical renferme des vésicules de diverses catégories.
Some ultrastructural data about a myoepithelium: The pharynx of a bryozoan
Summary Pharyngeal cells of Alcyonidium polyoum (Bryozoa) are provided with very large vacuoles. Each vacuole is enveloped by a thin layer of striated muscle, whose contraction enlarges the organ. Filaments join the muscular elements to the apical plasmalemma. This point of muscular insertion is connected by fibrils with the amorphic lamina of cell-coat which surrounds the microvilli. Ribosomes are often found on dyads. Various vesicles are located in the apical cytoplasm.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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Properties of the 12-O-Tetradecanoylphorbol-13-Acetate-Stimulated S6 Kinase from Rat Astroglial Cells 总被引:1,自引:0,他引:1
Danièle Toru-Delbauffe Jean-Michel Gavaret Claude Jacquemin Carole Matricon Martine Pomerance Michel Pierre 《Journal of neurochemistry》1988,51(5):1448-1454
The S6 kinase activity of astroglial cells in primary culture stimulated by 12-O-tetradecanoylphorbol-13-acetate (TPA) has been studied. This activity was eluted as a single peak at 0.15 M NaCl from a DEAE-Sephacel column. The chromatography of this peak on phosphocellulose revealed an activity eluted at 0.15 M NaCl. This partially purified enzyme had a sedimentation coefficient of 3.7S; Km values were 2 X 10(-5) M for ATP and 10(-6) M for 40S ribosomal subunits. The optimal Mg2+ concentration requirement was 2-3 mM. Mn2+ and Co2+ could substitute for Mg2+ (optimum concentrations 1.5 and 0.8 mM, respectively), but these cations were strong inhibitors in the presence of Mg2+. The enzyme was inhibited by N-ethylmaleimide, indicating that it contained thiol groups. This S6 kinase used ATP, but not GTP, as a phosphate donor, and exhibited great specificity for S6 as phosphate acceptor. Whole histones and protamine were slightly phosphorylated whereas phosvitin, histone H1, and surprisingly the peptide Arg-Arg-Leu-Ser-Ser-Leu-Arg-Ala were not phosphorylated. The TPA-stimulated S6 kinase resembles the insulin-, fibroblast growth factor- and cyclic AMP-stimulated enzymes, suggesting that several pathways might activate the same entity. 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