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1.
Effects of low molecular weight polypeptides (M. W. lower 10,000) isolated from the calf thymus, cortex and white matter of the brain by extraction with acetic acid on the cellular and humoral immune responses were studied in experimental thymectomized mature CBA mice. Thymectomy reduced markedly the number of T-cells in the spleen. Accordingly, the ability to generate both Ig M and IgG antibody forming cells as well as humoral antibodies to thymus-dependent antigen, SRBC, was significantly suppressed in the animals. Subcutaneous administration of 1 micron/g (body weight) of the thymus and brain cortex polypeptides during 8 days not only completely restored T-cells population in the spleen and immune responsibility but also elevated these values 1.5-2 fold in comparison with sham controls which had been given saline solution. The preparation from the white matter of the brain lacked biological activity.  相似文献   

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Rabbit antisera against low molecular weight polypeptides from the thymus (thymosin and thymarin), cortex (cortexin) and white matter of the brain of the calves were cross-absorbed with these polypeptides and tested in the complement fixation test with these preparations and in the complement-dependent cytotoxicity test with thymic and bone marrow cells. The results showed that thymosin, thymarin and cortexin are antigenically similar, but differ in antigenic structure from polypeptide from white matter of the brain. Biological effect of polypeptides from the thymus and brain cortex is connected with thymus-depending lymphocytes and does not depend on B-cells. Cross absorbtion revealed that antisera against polypeptides from thymus and cortex of the brain contain antibody both against common antigens and antigens specific for appropriate preparation only. Antigenic set of polypeptide from the thymus (thymarin) corresponds more closely to thymic antigen as compared to polypeptide from the brain cortex (cortexin).  相似文献   

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Effects of taurine on Ca++ binding to microsomes isolated from rat cerebral cortex were investigated in a medium containing various concentrations of KCl and/or NaCl. Calcium binding to microsomes was inhibited in a dose-dependent fashion by taurine in the incubation medium containing 5 mM KCl and 115 mM NaCl, while there was no inhibition in the medium containing 115 mM KCl and 5 mM NaCl. Taurine also decreased Ca++ binding in the medium containing 70 mM KCl without NaCl. A similar tendency toward inhibition of the Ca++ binding was observed in the medium with 5 mM or 120 mM KCl without NaCl. Taurine did not influence the Ca++ binding in the medium containing different concentrations of NaCl without KCl, or in the medium from which KCl and NaCl were omitted. Isethionate, glycine, γ-aminobutyric acid, β-alanine and L-leucine did not significantly alter the Ca++ binding to microsomes in the medium containing 70 mM KCl without NaCl. Thus it would appear that taurine may modulate the binding of calcium to microsomes in conditions which resemble the state of depolarization, while it is inactive in the normal resting state. This effect is apparently specific to taurine amongst a series of putative “inhibitory” amino acids.  相似文献   

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A study was made of the effects of the neurotransmitters acetylcholine and adrenaline on proliferation of B lymphocytes of mice immunized with ovalbumin. The neurotransmitters were noticed to be capable of changing B cell proliferation on cultivation in vitro. The effect (an increase or reduction of 3H-thymidine incorporation) depended on the time of immunization, antigen dose, and the type of a neurotransmitter. On the whole the pattern of the acetylcholine effect correlated with a natural trend of changes in B lymphocyte proliferation at different times of the immune response. Adrenaline produced a reciprocal effect.  相似文献   

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The influence of different peptide fractions obtained from the intact and latex-stimulated neutrophils on the immune response was studied. It was demonstrated that neutrophils after stimulation synthesize the factors activating immune response, the intact neutrophils synthesize the suppressor factors of peptide nature.  相似文献   

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Abramov VV  Abramova TJ  Kozlov VA 《Cytokine》2000,12(7):1147-1150
The objective of the investigation was to study the influence of RNA isolated from the brains of immunized mice on the immune response in syngeneic recipients. (CBAxC57BL/6)F1 male mice immunized by SRBC and RRBC were used for isolation of experimental RNA. Mice injected with medium 199 were used for isolation of control RNA. Experimental and control RNA was injected into syngeneic mice recipients immunized by SRBC, RRBC or rat RBC preliminary. It was shown that experimental RNA stimulate the specific immune response only.  相似文献   

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Effect of anthelminthic treatment on the immune response of mice   总被引:1,自引:0,他引:1  
Immunologic function was tested both in vivo and in vitro in mice undergoing prophylactic anthelminthic therapy with three agents to assess whether these drugs affected immune responses. This study was performed because investigators often are concerned about the effect of drug treatment on the induction of specific immune responses. While helminthic infestation is recognized as deleterious to the host, it is unclear whether anthelminthic treatment might be immunosuppressive. The effects of piperazine or trichlorphon administered to drinking water or fenbendazole administered in feed were insignificant in BALB/c mice. The induction of allospecific cytolytic T lymphocytes (CTLs) in vitro, influenza specific memory T cells in vivo, influenza specific antibody secretion in vivo, or influenza-specific helper T cells and CTLs in vitro were examined. Results of this study indicate that anthelminthic treatments did not interfere with immune responses.  相似文献   

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High hydrostatic pressure has been shown to produce neurological changes in humans which manifest, in part, as tremor, myoclonic jerks, electroencephalographic changes, and convulsions. This clinical pattern has been termed high-pressure nervous syndrome (HPNS). These symptoms may represent an alteration in synaptic transmission in the central nervous system with the inhibitory neural pathways being affected in particular. Since gamma-aminobutyric acid (GABA) transmission has been implicated in other seizure disorders, it was of interest to study GABAergic function at high pressure. Isolated synaptosomes were used to follow GABA release at 67.7 ATA of pressure. The major observation was a 33% depression in total [3H]GABA efflux from depolarized cerebrocortical synaptosomes at 67.7 ATA. The Ca2+-dependent component of release was found to be completely blocked during the 1st min of [3H]GABA efflux with a slow rise over the subsequent 3 min. These findings lead us to conclude that high pressure interferes with the intraterminal cascade for Ca2+-dependent release of GABA.  相似文献   

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The effect of in vitro exposure to low-power laser light with a power density of 0.2 mW/cm2 and a wavelength of 632.8 nm induced by helium-neon laser on the functional activity of macrophages and splenic lymphocytes was studied. If the exposure period did not exceed 60 sec, the stimulation in interleukin-2 (IL-2) and nitric oxide (NO) production, as well as an increase in the activity of natural killer cells were observed. The increase of irradiation dose by prolongation of the exposure duration up to 180 s induced a significant decrease in NO production and natural killer cell activity, but IL-2 production was not different from the control level. A remarkable decrease in interferon-gamma (IFN-gamma) production was observed following laser light exposure of cells for 60 or 180 s, whereas under lower doses (exposure for 5 or 30 sec) IFN-gamma production increased. Irradiation of isolated macrophages induced a significant stimulation of cellular tumor necrosis factor-alpha (TNF- alpha) production at all dboes used, and, what is more important, an enhancement in both TNF-a phaand interleukin-6 (IL-6) production was revealed as early as after a 5-s exposure. In this case, more prolonged exposure periods, 60 and 180 s, either did not induce changes in IL-6 production (in macrophages) or decreased IL-6 production (in lymphocytes). Thus, upon in vitro exposure of cells to extremely low-power laser light, a basic tendency was observed: short-term irradiation predominantly induced stimulation in secretory activity of cells, whereas prolongation of exposure mainly induced immunosuppression. The only exception to the rule was a change in interleukin-3 (IL-3) production, which decreased after short-time exposure, but, on the opposite, increased when the cells were exposed for 180 s. In addition, a high sensitivity to extremely low-power laser light was supported by expression of the inducible heat shock protein, Hsp70, the effect being observed at all doses used, including the exposure for 5 s. At the same time, expression of another heat shock protein, Hsp90, was somewhat reduced after irradiation of cells with laser light.  相似文献   

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The binding of alpha-human atrial natriuretic polypeptide (alpha-hANP) to brush border and basolateral membranes isolated from the rat renal cortex was studied at 0 degree C by a rapid filtration technique. Specific binding of 125I-alpha-hANP to basolateral membranes reached a steady state at 4 hr. The binding to brush border membranes was maximal at 5-15 min and then rapidly decreased. The analysis of incubation mixtures with basolateral membranes revealed little degradation of 125I-alpha-hANP during the 4-hr incubation, while there was extensive degradation of the ligand with brush border membranes during the 30-min incubation. High affinity binding of 125I-alpha-hANP was demonstrated on basolateral membranes but not on brush border membranes. These data suggest that specific receptors for alpha-hANP are localized on basolateral membranes of the renal cortex.  相似文献   

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Experiments were conducted on mice. Direct Jerne's test demonstrated a possibility of intensification of the primary immune response in the sexually mature mice under the effect of the splenic extracts. The significance of the extract dose and of the time of administration for the manifestation of the stimulating action was studied.  相似文献   

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Muscarinic acetylcholine receptors were solubilized from bovine cerebral cortex with 3-[(3-cholamidopropyl)-dimethylammonio]-1-propane sulfonate. The so-obtained receptors could be precipitated by Wheat Germ (73%), Concanavalin A (55%), Lens Culinaris (36%) and Ricinus Communis (26%), but not by Peanut, Dolichus Biflorus and Ulex Europaeus. On Wheat Germ- and Concanavalin A-affinity chromatography, the solubilized muscarinic receptors were retained on both columns and subsequently eluted with N-acetylglucosamine and alpha-methyl-D-mannoside, respectively. A high concentration (100 micrograms/ml) of Wheat Germ or Concanavalin A did not interfere with Z-[3H]quinuclidinyl benzilate binding, thereby suggesting that the lectin binding sites are not directly involved in the receptor binding function. These solubilized muscarinic receptors are postulated to contain carbohydrate residues, N-acetyl-glucosamine, mannose and galactose, as glycoprotein.  相似文献   

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