• Title, Summary, Keyword: oxide(NO)

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Analysis of Blood Flow-dependent Blood Nitric Oxide Level and Half-life of Nitric Oxide in Vivo

  • Kim Cuk-Seong;Kim Hyo-Shin;Lee Young-Jun;Park Jin Bory;Ryoo Sung-Woo;Chang Seok-Jang;Jeon Byeong-Hwa
    • International Journal of Vascular Biomedical Engineering
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    • v.1 no.2
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    • pp.13-19
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    • 2003
  • Endothelial release of nitric oxide (NO) contributes to the regulation of vascular tone by inducing vascular relaxation. To estimate the blood flow-dependent nitric oxide level and half-life (T1/2) of nitric oxide in vivo state, we investigated the change of aortic NO currents during the change of aortic blood flow rate using NO-selective electrode system and electromagnetic flowmeter in the aorta of anesthetized rats. Resting mean aortic blood flow rate was $49.6{\pm}5.6ml/min$ in the anesthetized rats. NO currents in the aorta were increased by the elevation of blood pressure and/or blood flow rate. When the aortic blood flow was occluded by the clamping, aortic NO currents were decreased. The difference of NO concentration between resting state and occluded state was $1.34{\pm}0.26{\mu}M$ (n=7). This NO concentration was estimated as blood flow-dependent nitric oxide concentration in the rats. Also, while the aortic blood flow was occluded, NO currents were decreased with exponential pattern with $12.84{\pm}2.15$ seconds of time constant and $7.70{\pm}1.07$ seconds of half-life. To summarize, this study suggested that blood flow-dependent NO concentration and half-life of nitric oxide were about $1.3{\mu}M$ and 7.7 seconds, respectively, in the aorta of anesthetized rats. The nitric oxide-selective electrode system is useful for the direct and continuous measurement of NO in vivo state.

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Characteristics of the NO/$N_2O$ Nitrided Oxide and Reoxidized Nitrided Oxide for NVSM (비휘발성 기억소자를 위한 NO/$N_2O$ 질화산화막과 재산화 질화산화막의 특성에 관한 연구)

  • 이상은;서춘원;서광열
    • Journal of the Korean Vacuum Society
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    • v.10 no.3
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    • pp.328-334
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    • 2001
  • The characteristics of $NO/N_2O$ nitrided oxide and reoxidized nitrided oxide being studied as super thin gate oxide and gate dielectric layers of nonvolatile semiconductor memory(NVSM) was investigated by dynamic secondary ion mass spectrometry(D-SMS), time-of-flight secondary ion mass spectrometry(ToF-SIMS), and x-ray photoelectron spectroscopy (XPS). The specimen was annealed in $NO/N_2O$ ambient after initial oxide process. The result of D-SIMS exhibits that the center of nitrogen exists at the initial oxide interface and the distribution of nitrogen is wider in the annealing process with $N_2O$ than with NO annealing process. For investigating the condition of nitrogen that exists within the nitrided oxide, ToF-SIMS and XPS analysis were carried out. It was shown that the center of nitrogen investigated by D-SIMS was expected the SiON chemical bonds. The nitrogen near the newly formed reoxide/silicon substrate interface was appeared as $Si_2NO$ chemical bonds, and it is agreed with the distribution of SiN and $Si_2NO$ species by ToF-SIMS.

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Verticillium dahliae toxins-induced nitric oxide production in Arabidopsis is major dependent on nitrate reductase

  • Shi, Fu-Mei;Li, Ying-Zhang
    • BMB Reports
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    • v.41 no.1
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    • pp.79-85
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    • 2008
  • The source of nitric oxide (NO) in plants is unclear and it has been reported NO can be produced by nitric oxide synthase (NOS) like enzymes and by nitrate reductase (NR). Here we used wild-type, Atnos1 mutant and nia1, nia2 NR-deficient mutant plants of Arabidopsis thaliana to investigate the potential source of NO production in response to Verticillium dahliae toxins (VD-toxins). The results revealed that NO production is much higher in wild-type and Atnos1 mutant than in nia1, nia2 NR-deficient mutants. The NR inhibitor had a significant effect on VD-toxins-induced NO production; whereas NOS inhibitor had a slight effect. NR activity was significantly implicated in NO production. The results indicated that as NO was induced in response to VD-toxins in Arabidopsis, the major source was the NR pathway. The production of NOS-system appeared to be secondary.

Nitric oxide production and inducible nitric oxide synthase expression induced by Porphyromonas gingivalis lipopolysaccharide (Porphyromonas gingivalis의 세균내독소가 RAW264.7세포에서의 nitric oxide의 생성과 inducible nitric oxide synthase의 발현에 미치는 영향 및 기전)

  • Paek, Eun-Young;Choi, Eun-Young;Choi, Jeom-II;Lee, Ju-Yun;Kim, Sung-Jo
    • Journal of Periodontal and Implant Science
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    • v.35 no.4
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    • pp.1081-1095
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    • 2005
  • 본 연구는 치주질환 주요 병인균주 중의 하나인 Porphyromonas gingivalis의 세균내독소가 마우스 대식 세포주인 RAW264.7 세포에서의 nitric oxide의 생성과 iNOS의 발현에 미치는 영향을 분석하고 그 기전을 규명하기 위해 수행되었다. Butanol추출법과 phenol-water법에 의해 P. gingivalis 381로부터 세균내독소를 추출하였으며, NO의 생성은 배양 상층액 내의 nitrite 농도를 측정하여 결정하였다. 또한, iNOS의 western blot 분석과 reverse transcription (RT)-PCR 산물의 분석을 수행하였다. P. gingivalis의 세균내독소는 부가적인 자극이 없는 상태에서도 iNOS의 발현과 NO 생성을 유발하였으며, NF- ${\kappa}B$, microtubule polymerization, protein tyrosine kinase, 그리고 protein kinase C 등이 P. gingivalis 세균내독소에 의한 NO 생성에 간여하는 것으로 여겨진다. 또한, P. gingivalis 세균내독소에 의한 NO 생성에는 L-arginine이 요구되었다. P. gingivalis 세균내독소에 의한 NO 생성은 염증성 치주질환의 발병과 진행에 있어 중요한 역할을 하는 것으로 여겨진다.

Hypoxia Enhances Nitric Oxide Synthesis by Upregulation of Inducible Nitric Oxide Synthase in Endothelial Cells

  • Rhee, Ki-Jong;Gwon, Sun-Yeong;Lee, Seunghyung
    • Biomedical Science Letters
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    • v.19 no.3
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    • pp.180-187
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    • 2013
  • Hypoxia is an integral part of the environment during luteolysis. In this study we examined whether hypoxia could directly stimulate endothelial cells to produce nitric oxide (NO). Endothelial cells were cultured in hypoxic (5% $O_2$) or normoxic (20% $O_2$) conditions and the levels of total NO, inducible NO and endothelial NO was measured. We found that hypoxia but not normoxia upregulated NO production. The increased NO levels correlated with increased inducible NO synthase (iNOS) expression whereas expression of endothelial NOS (eNOS) expression remained constant. Addition of the iNOS specific inhibitor 1400W to hypoxic cultures prevented NO production suggesting that hypoxia-induced NO production in endothelial cells was due mainly to upregulation of iNOS. We also found that prostaglandin $F_{2{\alpha}}$ (PGF) production was unaffected by hypoxia suggesting that upregulation of NO was not due to increased synthesis of PGF. In summary, we report that endothelial cells cultured under hypoxic conditions produce NO via the iNOS pathway. This study provides the importance of the relation between the hypoxic environment and the induction of NO by endothelial cells during regression of the corpus luteum in the ovary.

Therapeutic Application of Nitric Oxide in Human Diseases

  • NamKoong, Seung;Kim, Young-Myeong
    • Biomolecules & Therapeutics
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    • v.18 no.4
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    • pp.351-362
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    • 2010
  • Nitric oxide (NO), synthesized from L-arginine by three isoforms of NO synthase (NOS), is a gaseous signaling molecule with an astonishingly wide range of biological and pathophysiological activities, including vasorelaxation, angiogenesis, anti-inflammation, and anti-apoptosis in mammalian cells. Recent studies have shown that NO donors and inhaled NO convert to biologically active NO under biological conditions and act as a signaling molecule in pathophysiological conditions. This review will discuss the roles of NO and its potential therapeutic implication in various human diseases, such as tumor, vascular regeneration, hypertension, wound healing, and ischemia-reperfusion injury.

Role of Exogenous Nitric Oxide Generated through Microwave Plasma Activate the Oxidative Signaling Components in Differentiation of Myoblast cells into Myotube

  • Kumar, Naresh;Shaw, Priyanka;Attri, Pankaj;Uhm, Han Sup;Choi, Eun Ha
    • Proceedings of the Korean Vacuum Society Conference
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    • pp.158-158
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    • 2015
  • Myoblast are myogenic precursors that proliferate, activate, and differentiate on muscle injury to sustain the regenerative capacity of skeletal muscle; The neuronal isoform of nitric oxide synthase (nNOS, termed also NOS-I) is expressed in normal adult skeletal muscle, suggesting important functions for Nitric oxide (NO) in muscle biology1,2,3. However, the expression and subcellular localization of NO in muscle development and myoblast differentiation are largely unknown. In this study, we examined effects of the nitric oxide generated by a microwave plasma torch, on proliferation/differentiation of rat myoblastic L6 cells. Experimental data pertaining to nitric oxide production are presented in terms of the oxygen input in units of cubic centimetres per minute. The various levels of nitric oxide are observed depending on the flow rate of nitrogen gas, the ratio of oxygen gas, and the microwave power4. In order to evaluate the potential of nitric oxide as an activator of cell differentiation, we applied nitric oxide generated from the microwave plasma torch to L6 skeletal muscles. Differentiation of L6 cells into myotubes was significantly enhanced the differentiation after nitric oxide treatment. Nitric oxide treatment also increase the expression of myogenesis marker proteins and mRNA level, such as myogenin and myosin heavy chain (MHC), as well as cyclic guanosine monophosphate (cGMP), However during the myotube differentiation we found that NO activate oxidative stress signaling erks expression. Therefore, these results establish a role of NO and cGMP in regulating myoblast differentiation and elucidate their mechanism of action, providing a direct link with oxidative stress signalling, which is a key player in myogenesis. Based on these findings, nitric oxide generated by plasma can be used as a possible activator of cell differentiation and tissue regeneration.

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Effects of Nitric Oxide Modulating Drugs on Acrosome Reaction in Mouse Spermatozoa

  • Gye, Myung Chan
    • Animal cells and systems
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    • v.4 no.2
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    • pp.151-155
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    • 2000
  • Nitric oxide (NO) is a reactive free radical which plays important roles in animal physiology. To investigate involvement of NO in acrosome reaction (AR), effects of drugs which modulate the intracellular NO level were examined in mouse spermatozoa. N (G)-nitro-L-arginine (L-NA), a potent inhibitor of NO synthesis, decreased AR in a reversible manner, On the other hand, sodium nitroprusside (SNP), an NO generating agent, increased spontaneous AR. Preincubation of sperm in the presence of L-NA potentiated AR after sperm transfer into plain- or SNP-media. Methylene blue, a NO scavenging agent, decreased spontaneous AR. Taken together, it is concluded that NO positively controls AR.

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Inhibitory Effect of Galangin from Alpinia officinarum on Lipopolysaccharide-induced Nitric Oxide Synthesis in RAW 264.7 macrophages (고량강으로부터 분리된 galangin의 RAW 264.7 세포주에서 LPS로 유도된 nitric oxide 생성 저해활성)

  • Lee, Hwa Jin
    • Korean Journal of Food Science and Technology
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    • v.46 no.4
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    • pp.511-515
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    • 2014
  • In a screen for plant-derived inhibitors of nitric oxide (NO) production in lipopolysaccharide (LPS)-activated RAW 264.7 macrophage cells, a flavonol isolated from the chloroform extract of Alpinia officinarum was isolated. The structure of the flavonol was found to be 3,5,7-trihydroxy-2-phenylchromen-4-one (galangin, GLG) by using spectroscopy. GLG exhibited an inhibitory effect ($IC_{50}$ value: $26.8{\mu}M$) on NO production in LPS-stimulated RAW 264.7 murine macrophage cells. Moreover, GLG suppressed expressions of inducible nitric oxide synthase (iNOS) protein and mRNA in a dose-dependent manner.

The Effects of Diesel Exhaust Particles on the Alveolar Macrophages for Inducible Nitric Oxide Synthase Induction and Nitric Oxide with Nitrotyrosilated-protein Formation (디젤분진이 폐포대식세포에서 nitric oxide의 생성과 inducible nitric oxide synthase의 발현 및 nitrotyrosilated-protein의 형성에 미치는 효과)

  • Lim Young;Choe Myung-Ok;Lee Kweon-Haeng;Kim Kyung-A;Kim Kil-Soo;Lee Myoung-Heon;Li Tian-Zhu;Lee Soo-Jin;Choe Nong-Hoon
    • Journal of Life Science
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    • v.16 no.2
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    • pp.192-198
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    • 2006
  • Epidemiological studies have demonstrated an association between exposure to diesel exhaust particles (DEP) and adverse cardiopulmonary effects. Despite the epidemiological proof, the pathogenesis of DEP-related pulmonary diseases remain poorly understood. So, comprehensive in vivo and in vitro researches are required to know the effects of DEP on diverse lung diseases. Alveolar macrophages (AM) and airway epithelial cells are known as important cellular targets in DEP-induced lung diseases. Other studies have shown that nitric oxide (NO) is involved in particle matter induced lung injury. The present study was undertaken to determine whether DEP has an synergistic effects on lipopolysaccharide (LPS)-induced NO formation and inducible nitric oxide synthase (iNOS) with nitrotyrosilated-protein formation in cultured primary alveolar macrophages. The formation of NO was determined through the Griess reaction in the cultured medium and iNOS with nitrotyrosilated-proteins are analyzed by immunohistochemical staining and Western analysis. The results indicate that DEP exposure does not induce NO formation by itself, however DEP showed significant synergistic effects on LPS-induced NO formation. So, our results suggest that DEP inhalation could aggravate inflammatory lung disease through NO formation.