scholarly journals Activation of the TRKB receptor mediates the panicolytic-like effect of NOS inhibitor aminoguanidine

2018 ◽  
Author(s):  
DE Ribeiro ◽  
PC Casarotto ◽  
A Spiacci ◽  
GG Fernandes ◽  
LC Pinheiro ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Antidepressant Drugs ◽  
No Production ◽  
Periaqueductal Gray Matter ◽  
Nos Inhibitors ◽  
Escape Reaction ◽  
Nos Inhibitor ◽  
Bdnf Signaling ◽  
Oxide Synthase

AbstractNitric oxide (NO) triggers escape reactions in the dorsal periaqueductal gray matter (dPAG), a core structure mediating panic-associated responses, and decreases the release of BDNF in vitro. BDNF mediates the panicolytic effect induced by antidepressant drugs and produces these effects per se when injected into the dPAG. Based on these findings, we hypothesize that nitric oxide synthase (NOS) inhibitors would have panicolytic properties associated with increased BDNF signaling in the dPAG. We observed that the repeated (7 days), but not acute (1day), systemic administration of the NOS inhibitor aminoguanidine (AMG; 15 mg/kg/day) increased the latency to escape from the open arm of the elevated T-maze (ETM) and inhibited the number of jumps in hypoxia-induced escape reaction in rats, suggesting a panicolytic-like effect. Repeated, but not acute, AMG administration (15mg/kg) also decreased nitrite levels and increased TRKB phosphorylation at residues Y706/7 in the dPAG. Notwithstanding the lack of AMG effect on total BDNF levels in that structure, the microinjection of the TRK antagonist K252a into the dPAG blocked the anti-escape effect of this drug in the ETM. Taken together our data suggest that the inhibition of NO production by AMG increased the levels of pTRKB, which is required for the panicolytic-like effect observed.

scholarly journals Regulation of cyclooxygenase activity and progesterone production in the rat corpus luteum by inducible nitric oxide synthase

Reproduction ◽  
2002 ◽  
pp. 663-669 ◽  
Author(s):  
A Hurwitz ◽  
Z Finci-Yeheskel ◽  
A Milwidsky ◽  
M Mayer
Keyword(s):  
Nitric Oxide ◽  
Nitric Oxide Synthase ◽  
Corpus Luteum ◽  
Prostaglandin E ◽  
No Production ◽  
Luteal Cells ◽  
Progesterone Production ◽  
Nos Inhibitors ◽  
Nos Inhibitor ◽  
Oxide Synthase

This study explores interactions between the nitric oxide synthase (NOS) and the cyclooxygenase (COX) pathways in the regulation of progesterone production in early corpus luteum cells of rats. Nitric oxide (NO), prostaglandin E (PGE) and progesterone production was analysed in luteal cells of the rat corpus luteum exposed to inhibitors of non-specific NOS, inhibitors of inducible NOS (iNOS) and inhibitors of COX. Equine chorionic gonadotrophin (eCG)/hCG-primed rat corpus luteum cells produced NO, PGE and progesterone in a linear manner during 66 h of culture. Exposure of the cells to the non-specific NOS inhibitor, N(omega)-nitro-L-arginine (0.15 mmol l(-1)) for 48 h reduced NO, PGE and progesterone production to 21, 32 and 60% of that of the controls, respectively (P < 0.05 to P < 0.01). Another non-specific NOS inhibitor, N(omega)-methyl-L-arginine, produced similar inhibitions. Exposure of the cultured cells to S-ethylisothiourea (1 mmol l(-1)), a selective inhibitor of iNOS, suppressed the production of NO by 63%, PGE by 69% and progesterone by 48%. These findings indicate that production of PGE is regulated partly by iNOS, and that progesterone is probably regulated indirectly by the secondary changes in PGE. The addition of arachidonic acid to N(omega)-methyl-L-arginine-treated cells resulted in a significant increase in PGE and progesterone production (273 and 186%, respectively) without stimulating NO production. In contrast to the regulation exerted by the NO system on COX activity, the COX system does not modulate NO production in this model. This notion stems from the observation that the COX inhibitors acetylsalicylic acid (5 mmol l(-1)) and indomethacin (5 micromol l(-1)) suppressed PGE by 86 and 89%, respectively, and progesterone by 34 and 57%, respectively, but failed to inhibit NO production. The results from the present study indicate that iNOS-mediated NO production is involved in stimulating PGE synthesis in rat luteal cells, which may upregulate progesterone production.

scholarly journals Effects of chitosan on nitric oxide production and inducible nitric oxide synthase activity and mRNA expression in weaned piglets

2018 ◽  
Vol 60 (No. 8) ◽  
pp. 359-366
Author(s):  
J. Li ◽  
B. Shi ◽  
S. Yan ◽  
L. Jin ◽  
Y. Guo ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Mrna Expression ◽  
Inducible Nitric Oxide Synthase ◽  
No Production ◽  
Weaned Piglets ◽  
Inos Activity ◽  
Oxide Synthase ◽  
Inducible Nitric Oxide

The effects of chitosan on nitric oxide (NO) production and inducible nitric oxide synthase (iNOS) activity and gene expression in vivo or vitro were investigated in weaned piglets. In vivo, 180 weaned piglets were assigned to five dietary treatments with six replicates. The piglets were fed on a basal diet supplemented with 0 (control), 100, 500, 1000, and 2000 mg chitosan/kg feed, respectively. In vitro, the peripheral blood mononuclear cells (PBMCs) from a weaned piglet were cultured respectively with 0 (control), 40, 80, 160, and 320 &micro;g chitosan/ml medium. Results showed that serum NO concentrations on days 14 and 28 and iNOS activity on day 28 were quadratically improved with increasing chitosan dose (P &lt; 0.05). The iNOS mRNA expressions were linearly or quadratically enhanced in the duodenum on day 28, and were improved quadratically in the jejunum on days 14 and 28 and in the ileum on day 28 (P &lt; 0.01). In vitro, the NO concentrations, iNOS activity, and mRNA expression in unstimulated PBMCs were quadratically enhanced by chitosan, but the improvement of NO concentrations and iNOS activity by chitosan were markedly inhibited by N-(3-[aminomethyl] benzyl) acetamidine (1400w) (P&nbsp;&lt; 0.05). Moreover, the increase of NO concentrations, iNOS activity, and mRNA expression in PBMCs induced by lipopolysaccharide (LPS) were suppressed significantly by chitosan (P &lt; 0.05). The results indicated that the NO concentrations, iNOS activity, and mRNA expression in piglets were increased by feeding chitosan in a dose-dependent manner. In addition, chitosan improved the NO production in unstimulated PBMCs but inhibited its production in LPS-induced cells, which exerted bidirectional regulatory effects on the NO production via modulated iNOS activity and mRNA expression.

Hypothermia-induced cardioprotection using extended ischemia and early reperfusion cooling

2007 ◽  
Vol 292 (4) ◽  
pp. H1995-H2003 ◽  
Author(s):  
Zuo-Hui Shao ◽  
Wei-Tien Chang ◽  
Kim Chai Chan ◽  
Kim R. Wojcik ◽  
Chin-Wang Hsu ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Protein Kinase ◽  
Therapeutic Hypothermia ◽  
Optimal Timing ◽  
No Production ◽  
Early Reperfusion ◽  
No Signaling ◽  
Nos Inhibitor ◽  
Oxide Synthase ◽  
Pkc Activation

Optimal timing of therapeutic hypothermia for cardiac ischemia is unknown. Our prior work suggests that ischemia with rapid reperfusion (I/R) in cardiomyocytes can be more damaging than prolonged ischemia alone. Also, these cardiomyocytes demonstrate protein kinase C (PKC) activation and nitric oxide (NO) signaling that confer protection against I/R injury. Thus we hypothesized that hypothermia will protect most using extended ischemia and early reperfusion cooling and is mediated via PKC and NO synthase (NOS). Chick cardiomyocytes were exposed to an established model of 1-h ischemia/3-h reperfusion, and the same field of initially contracting cells was monitored for viability and NO generation. Normothermic I/R resulted in 49.7 ± 3.4% cell death. Hypothermia induction to 25°C was most protective (14.3 ± 0.6% death, P < 0.001 vs. I/R control) when instituted during extended ischemia and early reperfusion, compared with induction after reperfusion (22.4 ± 2.9% death). Protection was completely lost if onset of cooling was delayed by 15 min of reperfusion (45.0 ± 8.2% death). Extended ischemia/early reperfusion cooling was associated with increased and sustained NO generation at reperfusion and decreased caspase-3 activation. The NOS inhibitor Nω-nitro-l-arginine methyl ester (200 μM) reversed these changes and abrogated hypothermia protection. In addition, the PKCε inhibitor myr-PKCε v1-2 (5 μM) also reversed NO production and hypothermia protection. In conclusion, therapeutic hypothermia initiated during extended ischemia/early reperfusion optimally protects cardiomyocytes from I/R injury. Such protection appears to be mediated by increased NO generation via activation of protein kinase Cε; nitric oxide synthase.

Abstract 111: Xanthine Oxidoreductase Plays a Key Role in Nitrate, Nitrite and Nitric Oxide Homeostasis When the Endothelial Nitric Oxide Synthase is Compromised

Hypertension ◽  
2016 ◽  
Vol 68 (suppl_1) ◽  
Author(s):  
Maria Peleli ◽  
Christa Zollbrecht ◽  
Marcelo Montenegro ◽  
Michael Hezel ◽  
Eddie Weitzberg ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Blood Pressure ◽  
Primary Source ◽  
No Production ◽  
Xanthine Oxidoreductase ◽  
Physiological Conditions ◽  
Inorganic Nitrate ◽  
Nos Inhibitor ◽  
Oxide Synthase ◽  
Endothelial Nitric Oxide

Xanthine oxidoreductase (XOR) is generally known as a source of superoxide production, but this enzyme has also been suggested to mediate NO production via reduction of inorganic nitrate (NO 3 - ) and nitrite(NO 2 - ). This pathway for NO generation is of particular importance during certain pathologies, whereas endothelial NO synthase (eNOS) is the primary source of vascular NO generation under normal physiological conditions. The exact interplay between the NOS and XOR-derived NO is not yet fully elucidated. The aim of the present study was to investigate if eNOS deficiency is partly compensated by XOR upregulation and sensitization of the NO 3 - - NO 2 - - NO pathway. NO 3 - and NO 2 - were similar between naïve eNOS KO and wildtype (wt) mice, but reduced upon chronic treatment with the non-selective NOS inhibitor L-NAME (wt: 25.0±5.2, eNOS KO: 39.2±6.4, L-NAME: 8.2±1.6 μ NO 3 - -, wt: 0.38±0.07, eNOS KO: 0.42±0.04, L-NAME: 0.12±0.02 μ NO 2 - ). XOR function was upregulated in eNOS KO compared with wt mice [(mRNA: wt 1±0.07, eNOS KO 1.38±0.17), (activity: wt 825±54, eNOS KO 1327±280 CLU/mg/min), (uric acid: wt 32.87±1.53, eNOS KO 43.23±3.54 μ)]. None of these markers of XOR activity was increased in nNOS KO and iNOS KO mice. Following acute dose of NO 3 - (10 mg/kg bw, i.p.), the increase of plasma NO 2 - was more pronounced in eNOS KO (+0.51±0.13 μ) compared with wt (+0.22±0.09 μ), and this augmented response in the eNOS KO was abolished by treatment with the highly selective XOR inhibitor febuxostat (FEB). Liver from eNOS KO had higher reducing capacity of NO 2 - to NO compared with wt, and this effect was attenuated by FEB (Δppb of NO: wt +8.7±4.2, eNOS KO +44.2±15.0, wt+FEB +22.2±9.6, eNOS KO+FEB +26.8±10.2). Treatment with FEB increased blood pressure in eNOS KO (ΔMAP:+10.2±5.6 mmHg), but had no effect in wt (ΔMAP:-0.6±3.3 mmHg). Supplementation with NO 3 - (10 mM, drinking water) reduced blood pressure in eNOS KO (ΔMAP: -6.3±2.2 mmHg), and this effect was abolished by FEB (ΔMAP: +1.1±1.9 mmHg). In conclusion, upregulated and altered XOR function in conditions with eNOS deficiency can facilitate the NO 3 - - NO 2 - - NO pathway and hence play a significant role in vascular NO homeostasis.

scholarly journals Suppression of arthritis by an inhibitor of nitric oxide synthase.

1993 ◽  
Vol 178 (2) ◽  
pp. 749-754 ◽  
Author(s):  
N McCartney-Francis ◽  
J B Allen ◽  
D E Mizel ◽  
J E Albina ◽  
Q W Xie ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Inflammatory Responses ◽  
Inflammatory Cells ◽  
No Production ◽  
Streptococcal Cell Wall ◽  
Cell Mediated Immune Response ◽  
A Cell ◽  
Nos Inhibitor ◽  
Oxide Synthase ◽  
Articular Index

Nitric oxide (NO), a toxic radical gas produced during the metabolism of L-arginine by NO synthase (NOS), has been implicated as a mediator of immune and inflammatory responses. A single injection of streptococcal cell wall fragments (SCW) induces the accumulation of inflammatory cells within the synovial tissue and a cell-mediated immune response that leads destructive lesions. We show here that NO production is elevated in the inflamed joints of SCW-treated rats. Administration of NG-monomethyl-L-arginine, an inhibitor of NOS, profoundly reduced the synovial inflammation and tissue damage as measured by an articular index and reflected in the histopathology. These studies implicate the NO pathway in the pathogenesis of an inflammatory arthritis and demonstrate the ability of a NOS inhibitor to modulate the disease.

Parasite killing in murine malaria does not require nitric oxide production

Parasitology ◽  
1999 ◽  
Vol 118 (2) ◽  
pp. 139-143 ◽  
Author(s):  
N. FAVRE ◽  
B. RYFFEL ◽  
W. RUDIN
Keyword(s):  
Nitric Oxide ◽  
Blood Stage ◽  
No Production ◽  
Nos Inhibitor ◽  
Oxide Synthase ◽  
Deficient Mice ◽  
Stage Parasite ◽  
Blood Stage Malaria ◽  
Inducible Nitric Oxide

Nitric oxide (NO) production has been suggested to play a role as effector molecule in the control of the malarial infections. However, the roles of this molecule are debated. To assess whether blood-stage parasite killing is NO dependent, we investigated the course of blood-stage Plasmodium chabaudi chabaudi (Pcc) infections in inducible nitric oxide synthase (iNOS)-deficient mice. Parasitaemia, haematological alterations, and survival were not affected by the lack of iNOS. To exclude a role of NO produced by other NOS, controls included NO suppression by oral administration of aminoguanidine (AG), a NOS inhibitor. As in iNOS-deficient mice, no difference in the parasitaemia course, survival and haematological values was observed after AG treatment. Our results indicate that NO production is not required for protection against malaria in our murine experimental model. However, C57BL/6 mice treated with AG lost their resistance to Pcc infections, suggesting that the requirement for NO production for parasite killing in murine blood-stage malaria might be strain dependent.

scholarly journals Regulatory Role of GSK-3βon NF-κB, Nitric Oxide, and TNF-αin Group A Streptococcal Infection

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Yu-Tzu Chang ◽  
Chia-Ling Chen ◽  
Chiou-Feng Lin ◽  
Shiou-Ling Lu ◽  
Miao-Huei Cheng ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Mouse Model ◽  
Group A Streptococcus ◽  
Glycogen Synthase ◽  
Critical Issue ◽  
No Production ◽  
Group A ◽  
Oxide Synthase

Group A streptococcus (GAS) imposes a great burden on humans. Efforts to minimize the associated morbidity and mortality represent a critical issue. Glycogen synthase kinase-3β(GSK-3β) is known to regulate inflammatory response in infectious diseases. However, the regulation of GSK-3βin GAS infection is still unknown. The present study investigates the interaction between GSK-3β, NF-κB, and possible related inflammatory mediators in vitro and in a mouse model. The results revealed that GAS could activate NF-κB, followed by an increased expression of inducible nitric oxide synthase (iNOS) and NO production in a murine macrophage cell line. Activation of GSK-3βoccurred after GAS infection, and inhibition of GSK-3βreduced iNOS expression and NO production. Furthermore, GSK-3βinhibitors reduced NF-κB activation and subsequent TNF-αproduction, which indicates that GSK-3βacts upstream of NF-κB in GAS-infected macrophages. Similar to the in vitro findings, administration of GSK-3βinhibitor in an air pouch GAS infection mouse model significantly reduced the level of serum TNF-αand improved the survival rate. The inhibition of GSK-3βto moderate the inflammatory effect might be an alternative therapeutic strategy against GAS infection.

scholarly journals 108 THE ROLE OF NITRIC OXIDE SYNTHASE IN IN VITRO DEVELOPMENT OF BOVINE OOCYTES AND PRE-IMPLANTATION EMBRYOS

2005 ◽  
Vol 17 (2) ◽  
pp. 204
Author(s):  
A.K. Kadanga ◽  
D. Tesfaye ◽  
S. Ponsuksili ◽  
K. Wimmers ◽  
M. Gilles ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Culture Medium ◽  
Bovine Embryos ◽  
Nos Inhibitor ◽  
Blastocyst Rate ◽  
Oxide Synthase ◽  
Vitro Development ◽  
Bovine Oocytes

Nitric oxide (NO) is a free radical that serves as a key-signal molecule in various physiological processes including reproduction. Four isoforms of nitric oxide synthase (NOS) have been characterized: endothelial (eNOS), inducible (iNOS), neuronal (nNOS), and mitochondrial (mtNOS). The first two isoforms are reported to be expressed in mouse follicles, oocytes, and pre-implantation embryos (Nishikimi A et al. 2001 Reproduction 122, 957–963). However, the role of any of these isoforms have not yet been investigated in bovine embryos. Here we aimed to examine the role of NOS in in vitro development of bovine embryos by treating embryos with NOS inhibitor, N-omega-L-nitro-arginine methyl esther (L-NAME), and examining the localization of the protein in pre-implantation embryos. Oocytes and embryos were grown in the media with NOS inhibitor added at a level of 0 mM (control), 1 mM, and 10 mM to either maturation or culture medium. Each experiment was conducted in four replicates each containing 100 oocytes for IVP. Cleavage and blastocyst rate were recorded at Days 2 and 7, respectively. Data were analyzed using the General Linear Model in SAS version 8.02 (SAS Institute, Inc., Cary, NC, USA) with the main factors being the level of L-NAME and the point of application. Pairwise comparisons were done using the Tukey test. Protein localization in bovine oocytes and embryos was performed by immunocytochemistry using eNOS- and iNOS-specific antibodies. Embryos were fixed in 3.7% paraformaldehyde, permeabilized in 0.1% Triton-X100, and washed three times in PBS supplemented with BSA. They were incubated with eNOS and iNOS primary antibody (1:200 dilutions) and washed before incubation with secondary antibody conjugated to FITC. After washing they were mounted on glass slides and examined under a confocal laser scanning microscope (Carl Zeiss Jena, Carl Zeiss AG, Oberkochen, Germany). In the controls the primary antibodies were omitted. As shown in the table below, the presence of L-NAME in the maturation medium significantly reduced the cleavage and blastocyst rate independent of the dosage applied. However the presence of L-NAME in the culture medium had an influence only on the blastocyst rate. The immunocytochemical staining results showed that both eNOS and iNOS are expressed in the cytoplasm of the MII oocytes, and during the pre-implantation stage the fluorescence signal was observed in nuclei and cytoplasm. However, the nuclear signal was much weaker. In conclusion, the present study is the first to determine the role of NO and to detect NOS protein in bovine oocytes and pre-implantation embryos. These results indicate that nitric oxide may play an important role as diffusible regulator of bovine oocyte maturation and preimplantation embryo development. Table 1. Effect of l-name addition in maturation or culture medium on embryo development

Leakage responses to l-NAME differ with the fluorescent dye used to label albumin

1999 ◽  
Vol 276 (1) ◽  
pp. H333-H339 ◽  
Author(s):  
Rolando E. Rumbaut ◽  
Norman R. Harris ◽  
Arshad J. Sial ◽  
Virginia H. Huxley ◽  
D. Neil Granger
Keyword(s):  
Nitric Oxide ◽  
Fluorescent Dyes ◽  
Albumin Leakage ◽  
Nos Inhibitors ◽  
Microvascular Transport ◽  
Nos Inhibitor ◽  
Sulforhodamine 101 ◽  
Oxide Synthase ◽  
Texas Red ◽  
Transport Of Macromolecules

Nitric oxide synthase (NOS) inhibitors have been reported to increase as well as to decrease microvascular transport of macromolecules in a variety of models. This study was performed to determine whether the influence of NOS inhibition on albumin leakage was dependent on the fluorescent dyes used to label albumin. Albumin leakage was assessed in rat mesenteric venules during control conditions and after exposure to the NOS inhibitor N G-nitro-l-arginine methyl ester (l-NAME). Albumin was labeled with any one of four dyes: FITC, sulforhodamine 101 [Texas Red (TR)], dichlorotriazinyl aminofluorescein (DTAF), or Oregon Green 514 (OG). Superfusion withl-NAME (10−4 M) was accompanied by an increase in leakage of FITC-labeled albumin ( n = 12) but not of albumin labeled with DTAF ( n = 10), TR ( n = 10), or OG ( n = 4). In vessels perfused with both FITC- and TR-labeled albumin ( n = 12), superfusion with l-NAME increased leakage of FITC- but not TR-labeled albumin. In conclusion, albumin leakage responses tol-NAME differ among various fluorescent dyes. Therefore, caution is advised in comparison of albumin leakage results that utilize different fluorescent dyes.

scholarly journals Nitric Oxide Synthase Gene Transfer Overcomes the Inhibition of Wound Healing by Sulfur Mustard in a Human Keratinocyte In Vitro Model

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Hiroshi Ishida ◽  
Radharaman Ray ◽  
Jack Amnuaysirikul ◽  
Keiko Ishida ◽  
Prabhati Ray
Keyword(s):  
Nitric Oxide ◽  
Wound Healing ◽  
Nitric Oxide Synthase ◽  
Gene Transfer ◽  
Sulfur Mustard ◽  
No Production ◽  
Skin Injury ◽  
Inos Gene ◽  
Oxide Synthase

Sulfur mustard (SM) is a chemical warfare agent that causes extensive skin injury. Previously we reported that SM exposure resulted in suppression of inducible nitric oxide synthase (iNOS) expression to inhibit the healing of scratch wounds in a cultured normal human epidermal keratinocyte (NHEK) model. Based on this finding, the present study was to use adenovirus-mediated gene transfer of iNOS to restore the nitric oxide (NO) supply depleted by exposure to SM and to evaluate the effect of NO on wound healing inhibited by SM in NHEKs. The effect of the iNOS gene transfer on iNOS protein expression and NO generation were monitored by Western blot and flow cytometry, respectively. Wound healing with or without the iNOS gene transfer after SM exposure was assessed by light and confocal microscopy. The iNOS gene transfer via adenovirus resulted in overexpression of the iNOS and an increase in NO production regardless of SM exposure in the NHEK model. The gene transfer was also effective in overcoming the inhibition of wound healing due to SM exposure leading to the promotion of wound closure. The findings in this study suggest that the iNOS gene transfer is a promising therapeutic strategy for SM-induced skin injury.

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