共查询到20条相似文献,搜索用时 15 毫秒
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A. Martínez V. Riveros-Moreno J. M. Polak S. Moncada P. Sesma 《Cell and tissue research》1994,275(3):599-603
The neuroendocrine system of the starfish Marthasterias glacialis was investigated immunocytochemically using antisera specific for rat neuronal, bovine aortic endothelial, and mouse macrophage, nitric oxide (NO) synthases. Immunoreactivity was detected only with the antibodies specific for the neural enzyme, in the ectoneural and hyponeural tissues of the radial nerve cords and in the basiepithelial plexus and endocrine cells of the digestive tract. The pyloric stomach showed more immunoreactive structures than the other digestive organs, with the rectal caeca showing the least activity. Immunoreactive endocrine cells were located in the cardiac and pyloric stomachs and in the pyloric caeca. Co-localization of the enzyme immunoreactivity, and the staining for NADPH-diaphorase, demonstrate the presence of NO synthase in echinoderms. These results provide further evidence that NO is a neuronal messenger of early phylogenetic origin which has been conserved throughout evolution. 相似文献
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1-(5-Isoquinolinylsulfonyl)-2-methylpiperazine (H-7), a protein kinase inhibitor, suppressed interleukin 2 (IL-2) production and IL-2 receptor (IL-2R) expression of the human leukemic T-cell line, Jurkat, induced by 12-O-tetradecanoyl-phorbol-13-acetate and phytohemagglutinin-P. This effect was significant at 5 microM H-7 without loss of cell viability. Such activity was not observed with N-(2-guanidinoethyl)-5-isoquinolinesulfonamide (HA 1004), a potent inhibitor of cGMP- and cAMP-dependent kinases, and a weak inhibitor of Ca2+-phospholipid-dependent protein kinase (protein kinase C). These findings suggest that protein kinase C is more closely associated with IL-2 receptor expression and IL-2 production of T cells than cGMP- or cAMP-dependent kinases. In addition, N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7), a calmodulin inhibitor, suppressed both IL-2 production and IL-2R expression. Cycrosporin A (Cy A), a potent immunosuppressive drug, markedly inhibited IL-2 production of Jurkat cells whereas it did not affect the IL-2R expression. Thus, the mechanism of action of Cy A appears to differ from that of the protein kinase inhibitor, H-7, and the calmodulin inhibitor, W-7. 相似文献
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Nitric oxide (NO) serves as a retrograde messenger to activate neuronal NO synthase in the spinal cord via NMDA receptors. 总被引:2,自引:0,他引:2
Li Xu Tamaki Mabuchi Tayo Katano Shinji Matsumura Emiko Okuda-Ashitaka Kenji Sakimura Masayoshi Mishina Seiji Ito 《Nitric oxide》2007,17(1):18-24
We have recently demonstrated that nitric oxide (NO) produced by neuronal NO synthase (nNOS) in the spinal cord is involved in the maintenance of neuropathic pain. To clarify whether NO itself affected nNOS activity in the spinal cord as a retrograde messenger, we examined the involvement of the NO/cGMP signaling pathway in the regulation of nNOS activity by NADPH-diaphorase histochemistry. NO-generating agents NOR3 (t(1/2)=30min) and SNAP (t(1/2)=5h), but not NOR1 (t(1/2)=1.8min), significantly enhanced NADPH-diaphorase staining in the spinal cord. 8-Br-cGMP also enhanced it similar to that by NOR3, and 8-Br-cAMP and forskolin, an activator of adenylate cyclase, enhanced it moderately. NOR1 and NOR3 markedly increased the cGMP level in the spinal cord. The enhancement of NADPH-diaphorase staining by NOR3 was significantly inhibited by CPTIO, an NO scavenger, ODQ, a soluble guanylate cyclase inhibitor, and KT5823, an inhibitor of cGMP-dependent protein kinase. Additionally, the NOR3-enhanced nNOS activity was completely inhibited by NMDA antagonists MK-801 and d-AP5, partially by the GluRepsilon2-selective antagonist CP-101,606, and was attenuated in GluRepsilon1(-/-) and GluRepsilon1(-/-)/epsilon4(-/-) mice. These results suggest that NO may regulate nNOS activity as a retrograde messenger in the spinal cord via activation of NMDA receptor containing GluRepsilon1 and GluRepsilon2 subunits. 相似文献
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Jiupian Yang Yoshifumi Matsumoto Takeomi Etoh Sumio Iwai 《Plant signaling & behavior》2008,3(2):131-132
We investigated the role of nitric oxide (NO) in ABA-inhibition of stomatal opening in Vicia faba L. in different size dishes. When a large dish (9 cm diameter) was used, ABA induced NO synthesis and the NO scavenger reduced ABA-inhibition of stomatal opening. When a small dish (6 cm diameter) was used, ABA induced stomatal closure and inhibited stomatal opening. The NO scavenger was able to reduce ABA-induced stomatal closure, but unable to reverse ABA-inhibition of stomatal opening. Furthermore, NO was not synthesized in response to ABA, indicating that NO is not required for ABA-inhibition of stomatal opening in the small dish. These results indicated that an NO-dependent and an NO-independent signaling pathway participate in ABA signaling pathway. An NO-dependent pathway is the major player in ABA-induced stomatal closure. However, in ABA-inhibition of stomatal opening, an NO-dependent and an NO-independent pathway act: different signaling molecules participate in ABA-signaling cascade under different environmental condition.Key words: ABA, environmental condition, nitric oxide, stomata, Vicia faba LNitric oxide (NO) is a key signaling molecule in plants.1,2 It functions in disease resistance and programmed cell death,3,4 root development,5,6 and plant responses to various abiotic stresses.1,2,7,8 In addition, NO is required for stomatal closure in response to ABA in several species including Arabidopsis, Vicia faba, pea, tomato, barley, and wheat.9–11 ABA-inhibition of stomatal opening is a distinct process from ABA-induced stomatal closure.12,13 In V. faba, these two processes employ a similar signaling pathway; NO is also a second messenger molecule for ABA-inhibition of stomatal opening in a large dish.14 In this study, we examined the role of NO in ABA-inhibition of stomatal opening using different dish sizes. In a small dish, NO is not involved in ABA-inhibition of stomatal opening: the NO-independent signaling pathway is the major player in it. 相似文献
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The present study focuses on the expression level of N-myristoyl transferase (NMT) in the course of human immunodeficiency virus type-1 (HIV-1) infection. HIV-1 structural proteins were gradually expressed during the process of infection of the human T-cell line CEM, whereas the expression levels of NMT subsequently decreased under the same conditions. In addition, the chronically HIV-1-infected T-cell line CEM/LAV-1 exhibited low expression levels of NMT. We hypothesize that the decrease in the expression level of NMT due to HIV-1 infection may be related to the virus' strategy that leads to its persistent replication. 相似文献
10.
Optimization and evaluation of electroporation delivery of siRNA in the human leukemic CEM cell line
In order to study nucleoside analog activation in the CEM cell line, a transfection protocol had to be optimized in order
to silence an enzyme involved in nucleoside analog activation. Hematopoetic cell lines can be difficult to transfect with
traditional lipid-based transfection, so the electroporation technique was used. Field strength, pulse length, temperature,
electroporation media, siRNA concentration, among other conditions were tested in order to obtain approximately 70–80% mRNA
and enzyme activity downregulation of the cytosolic enzyme deoxycytidine kinase (dCK), necessary for nucleoside analog activation.
Downregulation was assessed at mRNA and enzyme activity levels. After optimizing the protocol, a microarray analysis was performed
in order to investigate whether the downregulation was specific. Additionally two genes were differentially expressed besides
the downregulation of dCK. These were however of unknown function. The leakage of intracellular nucleotides was also addressed
in the electroporated cells since it can affect the DNA repair mechansism and the efficiency of nucleoside analogs. Three
of these pools were increased compared to untreated, unelectroporated cells. The siRNA transfected cells with reduced dCK
expression and activity showed reduced sensitivity to several nucleoside analogs as expected. The multidrug resistance to
other drugs, as seen in nucleoside analog-induced resistant cells, was not seen with this model. 相似文献
11.
Park JH Na HJ Kwon YG Ha KS Lee SJ Kim CK Lee KS Yoneyama T Hatakeyama K Kim PK Billiar TR Kim YM 《The Journal of biological chemistry》2002,277(49):47073-47079
Nitric oxide (NO) regulates the biological activity of many enzymes and other functional proteins as well as gene expression. In this study, we tested whether pretreatment with NO regulates NO production in response to cytokines in cultured rat hepatocytes. Hepatocytes were recovered in fresh medium for 24 h following pretreatment with the NO donor S-nitroso-N-acetyl-d,l-penicillamine (SNAP) and stimulated to express the inducible NO synthase (iNOS) with interleukin-1beta and interferon-gamma or transfected with the human iNOS gene. NO pretreatment resulted in a significant increase in NO production without changing iNOS expression for both conditions. This effect, which did not occur in macrophages and smooth muscle cells, was inhibited when NO was scavenged using red blood cells. Pretreatment with oxidized SNAP, 8-Br-cGMP, NO(2)(-), or NO(3)(-) did not increase the cytokine-induced NO production. SNAP pretreatment increased cytosolic iNOS activity measured only in the absence of exogenous tetrahydrobiopterin (BH(4)). SNAP pretreatment suppressed the level of GTP cyclohydrolase I (GTPCHI) feedback regulatory protein (GFRP) and increased GTPCHI activity without changing GTPCHI protein level. SNAP pretreatment also increased total cellular levels of biopterin and active iNOS dimer. These results suggest that SNAP pretreatment increased NO production from iNOS by elevating cellular BH(4) levels and promoting iNOS subunit dimerization through the suppression of GFRP levels and subsequent activation of GTPCHI. 相似文献
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Nitric oxide (NO) and NO cycle in myocardium: molecular, biochemical and physiological aspects 总被引:2,自引:0,他引:2
Reutov VP Okhotin VE Shuklin AV Sorokina EG Kositsyn NS Gurin VN 《Uspekhi fiziologicheskikh nauk》2007,38(4):39-58
The article continues the series of our publications on the problem of nitric oxide (NO) and its cyclic conversion in mammals. This review is held to analysis of nitric oxide role in regulation of cardiovascular system and in alocation of NO-synthases in myocardium. Molecular, biochemical and cytophysiological aspects that linked, with spatial localization of NO-synthases and mechanisms of NO content regulation in myocardium are considered. The results of author's investigations along the cyclic convertion of NO and literature data about compartmentalization of NO-synthases in myocardium are included in this paper. The contradictory and dissimilar facts about regulatory and toxic role of nitric oxide in cardiovascular system are represented. 相似文献
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The purpose of this study was to characterize behavioral interactions between nitric oxide synthase (NOS) inhibitors and serotonergic 5-HT2 receptors. In the present study, NOS inhibitors, N(G)-nitro-L-arginine, N(G)-nitro-L-arginine methylester, N(G)-monomethyl-L-arginine, 7-nitroindazole, trifluoperazine and NO scavenger, methylene blue markedly enhanced 5-hydroxytryptamine (5-HT)-induced selective serotonergic behavior, the head twitch response (HTR), in mice. However NO generators, sodium nitroprusside, 3-morpholinosydnonimine and S-nitroso-N-acetylpenicillamine as well as NO precursor, L-arginine markedly inhibited 5-HT induced HTR in mice. In the previous study, it was demonstrated that the N-methyl-D-aspartate (NMDA) receptor antagonists markedly enhanced 5-HT-induced selective serotonergic behavior, HTR, whereas NMDA itself inhibited 5-HT-induced HTR in mice. In the present study, it was demonstrated that the inhibition by a NMDA receptor agonist, NMDA of 5-HT-induced HTR was reversed by the treatment with NOS inhibitors, N(G)-nitro-L-arginine and N(G)-nitro-L-arginine methylester. The suppressive action by a NO generator, S-nitroso-N-acetylpenicillamine of 5-HT-induced HTR was also reversed by the treatment with NMDA receptor antagonists, MK-801 and dextromethorphan. These results have shown that the NO system is located down stream of NMDA receptors involved in modulation of 5-HT2-mediated HTR. Therefore, the enhanced effects of NOS inhibitors on 5-HT-induced HTR support experimental evidence for the NO/5-HT2 as well as NMDA/5-HT2 receptor interactions indicating that NO plays an important role in the glutamatergic modulation of the serotonergic function at the 5-HT2 receptor. 相似文献
14.
Nitric oxide synthase (NOS) catalyzes the formation of nitric oxide (NO) from L-arginine. In this study, the cellular localization
of neuronal NOS (nNOS) activity in the human retina since fetal development was examined by immunohistochemistry. No detectable
staining in the fetal retina was present at 14 weeks of gestation (wg), the earliest age group examined. A centro-peripheral
gradient of development of nNOS immunoreactivity was evident at 16–17 wg, with the midperipheral retina showing nNOS immunoreactivity
in most of the cell types and the inner plexiform layer while the peripheral part demonstrated moderate immunoreactivity only
in the ganglion cell layer and photoreceptor precursors. A transient increase in nNOS immunoreactivity in the ganglion cells
and Müller cell endfeet between 18–19 and 24–25 wg was observed at the time when programmed cell death in the ganglion cell
layer, loss of optic nerve fibres as well as increase in glutamate immunoreactivity and parvalbumin (a calcium binding protein)
immunoreactivity in the ganglion cells was reported. These observations indicate that programmed cell death of ganglion cells
in the retina may be linked to glutamate toxicity and NO activity, as also suggested by others in the retina and cerebral
cortex.
The presence of nNOS immunoreactivity in the photoreceptors from 16–17 weeks of fetal life to adulthood indicates other functions,
besides their involvement in photoreceptor function of transduction and information processing. 相似文献
15.
Vo PA Lad B Tomlinson JA Francis S Ahluwalia A 《The Journal of biological chemistry》2005,280(8):7236-7243
Nitric oxide (NO) produced by inducible nitric oxide synthase (iNOS) is responsible for sepsis-induced hypotension and plays a major contributory role in the ensuing multiorgan failure. The present study aimed to elucidate the role of endothelial NO in lipopolysaccharide (LPS)-induced iNOS expression, in isolated rat aortic rings. Exposure to LPS (1 mug/ml, 5 h) resulted in a reversal of phenylephrine precontracted tone in aortic rings (70.7 +/- 3.2%). This relaxation was associated with iNOS expression and NF-kappaB activation. Positive immunoreactivity for iNOS protein was localized in medial and adventitial layers of LPS-treated aortic rings. Removal of the endothelium rendered aortic rings resistant to LPS-induced relaxation (8.9 +/- 4.5%). Western blotting of these rings demonstrated an absence of iNOS expression. However, treatment of endothelium-denuded rings with the NO donor, diethylamine-NONOate (0.1 mum), restored LPS-induced relaxation (61.6 +/- 6.6%) and iNOS expression to levels comparable with arteries with intact endothelium. Blockade of endothelial NOS (eNOS) activation using geldanamycin and radicicol, inhibitors of heat shock protein 90, in endothelium-intact arteries suppressed both LPS-induced relaxation and LPS-induced iNOS expression (9.0 +/- 8.0% and 2.0 +/- 6.2%, respectively). Moreover, LPS treatment (12.5 mg/kg, intravenous, 15 h) of wild-type mice resulted in profound elevation of plasma [NO(x)] measurements that were reduced by approximately 50% in eNOS knock-out animals. Furthermore, LPS-induced changes in vascular reactivity and iNOS expression evident in wild-type tissues were profoundly suppressed in tissues taken from eNOS knockout animals. Together, these data suggest that eNOS-derived NO, in part via activation of NF-kappaB, regulates iNOS-induction by LPS. This study provides the first demonstration of a proinflammatory role of vascular eNOS in sepsis. 相似文献
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J Al-Hijji Ellika Andolf Ricardo Laurini Satish Batra 《Reproductive biology and endocrinology : RB&E》2003,1(1):51
To investigate the possible role of nitric oxide (NO) produced locally or intramurally in the quiescence of the pregnant myometrium,
nitric oxide synthase (NOS) activity was measured in samples from first trimester (villous, and non villous-trophoblast),
term placenta and pregnant myometrium. Trophoblast tissue was obtained from psychosocial termination of pregnancy (9 – 12
weeks' gestation) whereas placenta and myometrium, from the same patient, at deliveries by Caesarean section. NOS activity
was measured in both cytosolic and particulate fractions by the formation of 14C-citrulline from 14C-arginine. Western immunoblotting was used to identify the endothelial NOS (eNOS) and neuronal (nNOS) isoforms. The activity
of NOS in particulate fractions from all preparations was considerably higher than the cytosolic fractions. Activity in all
fractions except the myometrium was highly Ca-dependent. More than 50% of particulate NOS from the myometrium was Ca-independent.
NOS activity was highest in the villous trophoblast and there was a significant difference between the villous and non-villous
trophoblast. In placenta and myometrium, NOS was 2–4 fold and 20–28-fold lower than the villous trophoblast, respectively.
Western blot analysis showed clearly eNOS in the particulate fraction and a weak eNOS band in the cytosolic fractions, whereas
nNOS was not detectable in any of the fractions. In view of the marginal activity of NOS in the myometrium, NO produced by
the trophoblast and placenta could play a significant role in maintaining uterine quiescence by paracrine effect. 相似文献
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George Deliconstantinos Vassiliki Villiotou John C. Stavrides 《Neurochemical research》1995,20(2):217-224
The association of [3H]-Met-enkephalin with synaptosomes isolated from rat brain cortex, when incubated for 30 min at 25°C follows a sigmoid path with a Hill coefficient h=1.25±0.04. Binding of Met-enkephalin into synaptosomes was saturable, with an apparent binding constant of 8.33±0.48 nM. At saturation, Met-enkephalin specific receptors corresponded to 65.5±7.2 nmol/mg synaptosomal protein. The Hill plot in combination with the biphasic nature of the curve to obtain the equilibrium constant, showed a moderate degree of positive cooperativity in the binding of Met-enkephalin into synaptosomes of at least one class of high affinity specific receptors. Met-enkephalin increased the lipid fluidity of synaptosomal membranes labelled with 1,6-diphenyl-1,3,5-hexatriene (DPH), as indicated by the steady-state fluorescence anisotropy [(ro/r)–1]–1. Arthenius-type plots of [(ro/r)–1]–1 indicated that the lipid separation of the synaptosomal membranes at 23.4±1.2°C was perturbed by Met-enkephalin such that the temperature was reduced to 15.8±0.8°C. Naloxone reversed the fluidizing effect of Met-enkephalin, consistent with the receptor-mediated modulation of membrane fluidity. Naloxone alone had no effect on membrane fluidity. NO release and cGMP production by NO-synthase (NOS) and soluble guanylate cyclase (sGC), both located in the soluble fraction of synaptosomes (synaptosol) were decreased by 82% and 80% respectively, after treatment of synaptosomes with Met-enkephalin (10–10–10–4 M). These effects were reversed by naloxone (10–4 M) which alone was ineffective in changing NO and cGMP production. We propose that Met-enkephalin achieved these effects through receptor mediated perturbations of membrane lipid structure and that inhibition of the L-Arg/NO/cGMP pathway in the brain may result in the antinociceptive effects of Met-enkephalin. 相似文献
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B H Johnson R R Dean S M Moran E B Thompson 《The Journal of steroid biochemistry and molecular biology》1992,42(1):1-9
We have studied the growth effects of conditioned media, interleukin-2 and PGE prostaglandin analogs on the glucocorticoid-sensitive human leukemic T-cell clone, CEM-C7. After 4 days, the glucocorticoid dexamethasone at approximately 10 nM kills 50% of CEM-C7 cells. To test the hypothesis that glucocorticoid-mediated lymphocytolysis was due to suppression of lymphokine expression only, we attempted to protect CEM-C7 cells from lysis by provision of lymphokine(s). Conditioned media from interleukin-2 secreting Jurkat T-cells as well as the glucocorticoid-insensitive, but receptor positive clone, CEM-C1, failed to prevent lymphocytolysis; exogenous interleukin-2 also did not provide protection. There were complex, biphasic interactions between dexamethasone and the synthetic PGEs, enisoprost and enisoprost free acid. Low doses of enisoprost alone (0.01 to 1 microgram/ml) stimulated growth, and in combinations completely reversed the growth inhibitory effects of 10 nM dexamethasone. Higher concentrations of enisoprost were inherently lethal and were additive to the steroid effect. Thus the glucocorticoid-induced lymphocytolysis in this human leukemic T-cell line may be modified biphasically by PGE prostaglandins, depending on their concentration. However, interleukin-2 or components in the conditioned media assayed had no effect in ameliorating the lethal response to glucocorticoid. 相似文献
19.
Imanishi N Andoh T Sakai S Satoh M Katada Y Ueda K Terasawa K Ochiai H 《Microbiology and immunology》2005,49(1):41-48
We investigated the inductive activity of infective influenza A/PR/8/34 (PR8) virus and its ether-split product (ESP) on the expression of inducible nitric oxide (NO) synthase (iNOS) and NO production in RAW264.7 (RAW) cells, a murine macrophage (M psi) cell line, and thioglycolate-elicited peritoneal M psi (TPM). In both cells, PR8 virus infection induced iNOS mRNA between 4 hr and 24 hr, attaining a peak value at 12 hr. In correlation with induction of iNOS mRNA, NO amounts increased significantly from 12 to 24 hr. Moreover, this study demonstrated that ESP with the same hemagglutination titer as PR8 virus could induce iNOS mRNA and NO production, although the inductive activity of ESP was weaker than that of PR8 virus. Considering the dual role (beneficial and detrimental roles) of NO on certain inflammatory disorders and virus infections, the inductive activity of influenza virus on the iNOS-mediated NO production independent of its infectivity might contribute to a modification of influenza virus infection. 相似文献