• Title/Summary/Keyword: nitric oxide

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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.

Expression of Vascular Endothelin-1 and Nitric Oxide Synthase in Fructose-fed Hypertensive Rats (과당식이 고혈압 흰쥐에서 혈관 Endothelin-1과 산화질소합성효소의 발현)

  • Paek, Yun-Woong;Kim, Myung-Hoon
    • Journal of Korean Physical Therapy Science
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    • v.9 no.4
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    • pp.45-52
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    • 2002
  • Rats that are fed a fructose-rich diet develop hypertension, insulin resistance, and hypertriglyceridemia. To elucidate whether altered expression levels of endothelin-1 and nitric oxide synthase are related to the development of insulin-resistant hypertension, we examined the present study. Male Sprague-Dawley rats were fed a fructose-rich diet for 5 weeks. Systolic blood pressure significantly increased in fructose-fed rats. While serum free fatty acid and plasma nitrite/nitrate levels did not significantly differ between the fructose-fed and control groups, plasma insulin and serum triglyceride concentrations significantly increased in the former. Endothelin-1 mRNA expression in the aorta increased in fructose-fed rats. Neither the protein expression of constitutive nitric oxide synthase nor that of inducible nitric oxide synthase were significantly affected by fructose feeding. However, nitrite/nitrate levels in the aorta were significantly increased. These results suggest that an increase in vascular endothelin-1 is an important contributing factor to the development of hypertension in fructose-fed rats. However, the vascular nitric oxide pathway may not be causally related to the development of fructose-induced hypertension.

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Role of Angiotensin II and Nitric Oxide in the Rat Paraventricular Nucleus

  • Yang, Eun-Kyoung
    • The Korean Journal of Physiology and Pharmacology
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    • v.5 no.1
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    • pp.41-46
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    • 2001
  • To investigate the mutual relationship between angiotensin II (Ang II) and nitric oxide (NO) in paraventricular nucleus (PVN), Ang II receptor type Ia $(AT_{1A}),$ type Ib $(AT_{1B}),$ endothelial constitutive nitric oxide synthase (ecNOS), and neuronal constitutive nitric oxide synthase (ncNOS) mRNA levels of rat PVN were measured after unilateral carotid artery ligation. $AT_{1A}$ and $AT_{1B}$ mRNA levels were markedly elevated 6 hrs after unilateral carotid artery ligation. Losartan injection $(10\;{\mu}g/0.3\;{\mu}l)$ into the PVN augmented of the increment of $AT_{1A}$ and $AT_{1B}$ mRNAs It also increased ecNOS gene expression. In addition, $AT_{1B}$ mRNA levels increased after N-nitro-L-arginine methyl ester (L-NAME) injection $(50\;{\mu}g/0.3\;{\mu}l)$ into the PVN. These results suggest that Ang II and NO in the rat PVN may interplay, at least in part, through regulation of gene expression of ecNOS and $AT_{1B},$ respectively.

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Roles of Nitric Oxide in Vestibular Compensation

  • Jeong, Han-Seong;Jun, Jae-Yeoul;Park, Jong-Seong
    • The Korean Journal of Physiology and Pharmacology
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    • v.7 no.2
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    • pp.73-77
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    • 2003
  • The effects of nitric oxide on the vestibular function recovery following unilateral labyrinthectomy (UL) were studied. Sprague-Dawley male rats, treated with nitric oxide liberating agent sodium nitroprusside (SNP) and NOS inhibitor $N^G$-nitro-L-arginine methyl ester (L-NAME), were subjected to destruction of the unilateral vestibular apparatus, and then spontaneous nystagmus was observed in the rat. To explore the effects of nitric oxide on the neuronal excitability, whole cell patch clamp technique was applied on isolated medial vestibular nuclear neurons. The frequency of spontaneous nystagmus in SNP treated rats was lesser than that of spontaneous nystagmus in control animals. In contrast, pre-UL treatment with L-NAME resulted in a significant increase in spontaneous nystagmus frequency. In addition, SNP increased the frequency of spontaneous action potential in isolated medial vestibular nuclear neurons. Potassium currents of the vestibular nuclear neurons were inhibited by SNP. After blockade of calcium dependent potassium currents by high EGTA (11 mM) in a pipette solution, SNP did not inhibit outward potassium currents. 1H-[1,2,4] oxadiazolo [4,3-a] quinozalin-1-one (ODQ), a specific inhibitor of soluble guanylyl cyclase, inhibited the effects of SNP on the spontaneous firing and the potassium current. These results suggest that nitric oxide after unilateral labyrinthectomy would help to facilitate vestibular compensation by inhibiting calcium-dependent potassium currents through increasing intracellular cGMP, and consequently would increase excitability in ipsilateral vestibular nuclear neurons.

Upregulation of Nitric Oxide Synthase Activity by All-trans Retinoic Acid and 13-cis Retinoic Acid in Human Malignant Keratinocytes

  • Moon, Ki-Young
    • Biomedical Science Letters
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    • v.25 no.2
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    • pp.196-200
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    • 2019
  • Effect of retinoids, i.e., all-trans retinoic acid and 13-cis retinoic acid, on the activity of nitric oxide synthase (NOS) was evaluated in human malignant keratinocytes to examine the possible correlation of retinoids with NOS activities. All-trans retinoic acid and 13-cis retinoic acid did not alter the nitric oxide (NO) production. However, in the presence of lipopolysaccharide (LPS, $1{\mu}g/mL$), they significantly increased NO release in a dose-dependent manner until 48 h at concentrations of $50{\sim}100{\mu}M$. The degree of upregulation of NO by all-trans retinoic acid and 13-cis retinoic acid increased up to 35% and 37%, respectively, compared to that by the control, which demonstrated the upregulation of LPS-inducible nitric oxide synthase (iNOS)-dependent generation of NO as well as showing a crucial link between retinoids-induced activity and NOS. Findings of this study now suggest that the upregulation of LPS-iNOS activity may be associated with modulation of retinoids-induced control of cellular developmental processes, which may produce new therapeutics of retinoids in the complexity of how NO affects human keratinocytes.

Effects of Acai Berry Ethanolic Extracts on Production of Nitric Oxide and Activity of Angiotensin Converting Enzyme Related to Blood Circulation (혈액순환과 관련하여 nitric oxide 생성과 angiotensin converting enzyme 활성에 미치는 Acai berry 에탄올 추출물의 영향)

  • Nam, Hyang;Lee, Su-Gyeong;Kim, Deok Won;Kim, Joo Wan;Kim, Ki Young;Kim, Sung Goo;Kim, Moon-Moo;Chung, Kyung Tae
    • Journal of Life Science
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    • v.23 no.6
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    • pp.743-750
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    • 2013
  • The aim of this study is to develop a supplementary therapeutic agent capable of promoting vascular circulation. The effects of Acai berry ethanolic extracts (ABEE) on activity of angiotensin converting enzyme from rabbit lung, production of nitro oxide in both murine macrophage cells and vascular endothelial cells as well as antioxidant effects were investigated in this study. First of all, it was observed the direct effects of ABEE on reducing power and antioxidant effect lipid peroxidation. In addition, ABEE showed a protective effect on DNA oxidation induced by hydroxyl radical. Furthermore, ABEE at 0.01% exerted approximately 50% inhibition on activity of angiotensin converting enzyme. ABEE increased the production of nitric oxide in endothelial cells, but decreased the induction of nitric oxide stimulated by lipopolysaccharide in microphage. The expression levels of superoxide dismutase (SOD)-2 and -3 were enhanced by ABEE treatment, however, the expression level of SOD-1 remained constant. Moreover, the expression level of nitric oxide synthases-1 (NOS-1), a constitutive enzyme, was increased by ABEE, but that of NOS-2, a inducible enzyme, was constant. It was also found that the level of Nrf-2, a transcription factor of SOD, was increased by ABEE. Therefore, these results demonstrate that ABEE could promote blood circulation via above actions, suggesting that may be helpful for health of blood vessel.

Effect of Heat Shock Protein 70 on Inducible Nitric Oxide Synthase during Sepsis in Rats (패혈증에서 Heat Shock Protein 70의 과도발현이 Inducible Nitric Oxide Synthase의 발현에 미치는 효과)

  • Lee, Yong Keun;Shin, Hyo-Keun;Kwon, Woon Yong;Suh, Gil Joon;Youn, Yeo Kyu
    • Journal of Trauma and Injury
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    • v.21 no.1
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    • pp.59-65
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    • 2008
  • Purpose: The aim of this study was to evaluate the effect of overexpression of heat shock protein 70 (HSP70) on the expression of inducible nitric oxide synthase and on the concentration of nitric oxide and to determine the mechanism for the relationship between HSP70 and inducible nitric oxide synthase (iNOS) in sepsis. Methods: Experiments were performed on male Sprague-Dawley rats, and sepsis was induced by using cecal ligation and puncture (CLP). Glutamine (GLN) or saline was administered 1 h after initiation of sepsis. We acquired serum and lung tissues from the rats 12 h or 24 h after initiation of sepsis. We analyzed the concentration of nitric oxide, the expression of HSP70 in the lung, and the gene expression of iNOS in the lung. Results: In CLP+GLN, glutamine given after initiation of sepsis enhanced the expression of HSP70 in the lung at 12 h (CLP+GLN vs. CLP:: $47.19{\pm}10.04$ vs. $33.22{\pm}8.28$, p = 0.025) and 24 h (CLP+GLN vs. CLP: $47.06{\pm}10.60$ vs. $31.90{\pm}4.83$, p = 0.004). In CLP+GLN, glutamine attenuated the expression of iNOS mRNA in the lung at 12 h (CLP+GLN vs. CLP: $4167.17{\pm}951.59$ vs. $5513.73{\pm}1051.60$, p = 0.025) and 24 h (CLP+GLN vs. CLP: $9,437.65{\pm}2,521.07$ vs. $18,740.27{\pm}8,241.20$, p = 0.016) and reduced the concentration of nitric oxide in serum at 12 h (CLP+GLN vs. CLP: $0.86{\pm}0.48$ vs. $3.82{\pm}2.53{\mu}mol/L$, p = 0.016) and 24 h (CLP+GLN vs. CLP: $0.39{\pm}0.25$ vs. $1.85{\pm}1.70{\mu}mol/L$, p = 0.025). Conclusion: The overexpression of HSP70 induced by the administration of glutamine in sepsis attenuated the gene expression of iNOS and reduced the concentration of nitric oxide.

Effect of Lactobacillus pentosus-Fermented Artemisiae Argi Folium on Nitric Oxide Production of Macrophage impaired with Various Toxicants (유산균발효애엽이 독성물질들로 유발된 대식세포의 일산화질소생성 감소에 미치는 영향)

  • Park, Wan-Su
    • Journal of Pharmacopuncture
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    • v.12 no.4
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    • pp.89-96
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    • 2009
  • Objectives : The purpose of this study is to investigate the effect of Water Extract from Lactobacillus pentosus-fermented ARTEMISIAE ARGI FOLIUM (AFL) on nitric oxide production of mouse macrophage Raw 264.7 cells impaired by various toxicants such as gallic acid, EtOH, nicotine, acetaminophen, and acetaldehyde. Methods : ARTEMISIAE ARGI FOLIUM was fermented with Lactobacillus pentosus and extracted by water. Nitric oxide production of mouse macrophage Raw 264.7 cells was measured by Griess reagent assay. Examined concentrations of AFL were 10, 50, 100, 200, 400 ug/mL. Results : The results of the experiment are as below. 1. AFL at the concentration of 400 ug/mL significantly recovered nitric oxide production which was reduced by gallic acid (100 uM) in Raw 264.7 cells. 2. AFL at the concentration of 200, 400 ug/mL significantly recovered nitric oxide production which was reduced by EtOH (100 uM) in Raw 264.7 cells. 3. AFL at the concentration of 400 ug/mL significantly recovered nitric oxide production which was reduced by nicotine (1mM) in Raw 264.7 cells. 4. AFL at the concentration of 200, 400 ug/mL significantly recovered nitric oxide production which was reduced by acetaminophen(2 mM) in Raw 264.7 cells. 5. AFL at the concentration of 200, 400 ug/mL significantly recovered nitric oxide production which was reduced by acetaldehyde (200 uM) in Raw 264.7 cells. Conclusions : AFL could be supposed to have the immune-enhancing activity related with nitric oxide production of macrophage impaired by various toxicants.

Nitric Oxide-Mediated Cytotoxicity of Manganese in Basal Ganglia Neuronal Cells (대뇌 기저핵 신경세포에서 Nitric Oxide를 매개로 한 망간의 세포독성)

  • Jung, Yong-Wook;Bae, Jae-Hoon;Song, Dae-Kyu;Park, Won-Kyun;Ko, Bok-Hyun;Kim, Doo-Hie;Shin, Dong-Hoon
    • Journal of Preventive Medicine and Public Health
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    • v.32 no.4
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    • pp.459-466
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    • 1999
  • Objectives:eurotoxicity is mediated by nitric oxide(NO) in the rat primary neuronal cultures and assess the effect of $Mn^{2+}$ on the N-methyl-D aspartate(NMDA) receptors. Methods: We have used 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT)assay to examine the effect of cytotoxicity of $MnCl_2$ in neuronal cells , NO production was determined by measuring nirites, a stable oxidation product of NO. The neurons in the rat that contains neuronal nitric oxide synthase(nNOS) were examined by immunofluorescence and confocal microscopy. The effects of $Mn^{2+}$ on the NMDA receptors was assesed by the whole cell voltage clamp technique. Results: We showed that the NO release and NOS expression was increased with 500uM $MnCl_2$ treatment and an NOS inhibitors, $N^G-nitro-L-arginine$, prevented neurotoxicity elicited by manganese. In the electrophysiological study, $Mn^{2+}$ does not block or activate the NMDA receptors and not pass through the NMDA receptors in a neurons of basal ganglia. Conclusions: It is concluded that manganese neurotoxicity in basal ganglia was partially mediated by nitric oxide in the cell culture model.

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Total ginsenosides suppress monocrotaline-induced pulmonary hypertension in rats: involvement of nitric oxide and mitogen-activated protein kinase pathways

  • Qin, Na;Yang, Wei;Feng, Dongxu;Wang, Xinwen;Qi, Muyao;Du, Tianxin;Sun, Hongzhi;Wu, Shufang
    • Journal of Ginseng Research
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    • v.40 no.3
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    • pp.285-291
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    • 2016
  • Background: Ginsenosides have been shown to exert beneficial pharmacological effects on the central nervous, cardiovascular, and endocrine systems. We sought to determine whether total ginsenosides (TG) inhibit monocrotaline (MCT)-induced pulmonary hypertension and to elucidate the underlying mechanism. Methods: MCT-intoxicated rats were treated with gradient doses of TG, with or without $N^G$-nitro-$\small{L}$-arginine methyl ester. The levels of molecules involving the regulation of nitric oxide and mitogen-activated protein kinase pathways were determined. Results: TG ameliorated MCT-induced pulmonary hypertension in a dose-dependent manner, as assessed by the right ventricular systolic pressure, the right ventricular hypertrophy index, and pulmonary arterial remodeling. Furthermore, TG increased the levels of pulmonary nitric oxide, endothelial nitric oxide synthase, and cyclic guanosine monophosphate. Lastly, TG increased mitogen-activated protein kinase phosphatase-1 expression and promoted the dephosphorylation of extracellular signal-regulated protein kinases 1/2, p38 mitogen-activated protein kinase, and c-Jun NH2-terminal kinase 1/2. Conclusion: TG attenuates MCT-induced pulmonary hypertension, which may involve in part the regulation of nitric oxide and mitogen-activated protein kinase pathways.